§22 S3: scope-role enforcement + collection-grain visibility (@S3) — v0.42.0

Implement slice S3 of the §22 three-tier refactor: the four-layer
most-permissive scope-role resolver (§B.2) over {owner, contributor}
grants at {global, project, collection}, with the §22.5 visibility gate
enforced at the collection grain.

- migration 030: memberships.scope_type += 'global' (the global RFC
  Contributor tier; sentinel scope_id '*').
- auth.effective_scope_role folds global → project → collection,
  most-permissive, no negative override; can_read_collection /
  can_contribute_in_collection / is_collection_superuser /
  can_create_collection gate reads, writes, admin, and create.
- collection-grain visibility: a gated collection is hidden from the
  public (404, omitted from the directory) yet visible+listed for a
  scope-role holder; a collection may be set only as strict or stricter
  than its project (public < unlisted < gated), validated at create and
  clamped at the mirror.
- entry-scoped authority (mark-reviewed, graduate, branch read/contribute,
  PR/discussion/contribution moderation) re-pointed from the project grain
  to the entry's collection.
- create-collection authority widened to a project/global-scope grant
  holder (§B.1), not only a deployment owner/admin.

Keystone reconciliation (session 0076): a plain granted account is a
granted *account*, not a write-everywhere global role; the implicit-public
write baseline is grandfathered onto the migration-seeded `default`
collection only, so the N=1 deployment loses no capability. Reinterprets
§B.1/§B.3 literally — flagged for the SPEC merge (S6).

Completes @S3 (C1.1–C1.8). Tests: test_s3_scope_roles_vertical.py (8 C.1
scenarios + visibility/strictness), test_migration_030_global_scope.py.
Full backend suite 493 passed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.dockerignore

@@ -0,0 +1,15 @@
+# Keep the preview build context lean + reproducible.
+.git
+.gitea
+**/__pycache__/
+**/*.pyc
+backend/.venv/
+backend/data/
+frontend/node_modules/
+frontend/dist/
+e2e/
+mockups/
+docs/
+*.md
+!VERSION
+.pytest_cache/

CLAUDE.md

@@ -1,3 +1,5 @@
+@~/.claude/wiggleverse.md
+
 # Working in rfc-app
 
 This is the framework — the software that hosts an RFC standardization

CONTRIBUTING.md

@@ -0,0 +1,407 @@
+# Contributing to rfc-app
+
+`rfc-app` is the framework that hosts RFC-shaped collections of
+documents — one repo per RFC, a meta repo per collection, a web app
+that turns the Git substrate into a writeable surface. The Open
+Human Model (OHM) deployment at `ohm.wiggleverse.org` is one
+instance. The framework is intended to host more.
+
+This document explains how to propose a change to the framework
+itself — a new endpoint, a schema migration, a UI affordance, a
+spec clarification. For changes to *content* hosted by a specific
+deployment (the OHM RFCs, the OHM roadmap), see that deployment's
+own contribution guide (e.g. [`ohm-rfc/CONTRIBUTING.md`](https://git.wiggleverse.org/wiggleverse/ohm-rfc/src/branch/main/CONTRIBUTING.md)).
+
+---
+
+## How the project actually evolves
+
+rfc-app is built in the open in the literal sense: **every build
+session produces a full transcript** at
+[`wiggleverse/ohm-session-history`](https://git.wiggleverse.org/wiggleverse/ohm-session-history)
+on `git.wiggleverse.org`. The transcripts are the authoritative
+record of how the framework got from one release to the next — the
+decisions, the friction, the dead ends, the reasoning. They are not
+curated retrospectives; wrong turns stay in.
+
+If you are proposing a change to rfc-app, **read at least the most
+recent session transcript before opening a PR.** The transcripts
+show what shape a feature lands in, where the spec gets touched,
+what the operator pushes back on, and how the release rides into
+deployment. A PR that matches that texture is much more likely to
+land cleanly than one shaped by the README alone.
+
+Worked examples to start with:
+
+- **Session E** ([transcript](https://git.wiggleverse.org/wiggleverse/ohm-session-history)) —
+  a clean small release. Read this for the simplest possible release
+  shape: one feature, one version bump, one upgrade-steps block, no
+  surprises.
+- **Session I** — recovery from a deploy fault. Read this for how
+  the project handles things going wrong mid-deploy, and for the
+  honest no-curation discipline.
+- **Session K** — a multi-feature wave with one item paused on an
+  operator-provided secret. Read this for the subagent dispatch
+  pattern (the model the project uses to ship multiple features in
+  parallel), and for the binding rule that the assistant **never**
+  asks the operator to paste secret bytes into the conversation.
+- **Session L** — squash-merge integration across three parallel
+  features (v0.15.0 / v0.16.0 / v0.17.0), with `#21 Part C`
+  identity-lifecycle Amplitude wiring folded inline across all
+  three releases. Read this for how cross-cutting concerns (analytics,
+  observability) get layered into already-in-flight features
+  without scope-creeping any single release.
+
+The repository where transcripts live —
+[`wiggleverse/ohm-session-history`](https://git.wiggleverse.org/wiggleverse/ohm-session-history) —
+is the canonical history. The `git log` of `rfc-app` is the artifact;
+the transcripts are the story behind it.
+
+---
+
+## How a contribution flows
+
+The framework runs on a **subagents push feature branches; operator
+tags and deploys** model. Contributors — whether human or AI agents
+running in a Claude Code subsession — open feature branches and
+submit PRs. The operator (the person running the deployment) is the
+one who merges, tags, bumps `VERSION`, runs `flotilla deploy` (or
+the equivalent for non-OHM deployments), and moves the deployment's
+`.rfc-app-version` pin. The driver session transcripts inherit
+this shape; contributors inherit it from them.
+
+Concretely:
+
+1. Read the most recent session transcript. Understand what just
+   shipped and what is in flight.
+2. Open an Issue first if your change is exploratory, structural,
+   or might overlap with in-flight work. The operator will name
+   any collision.
+3. Branch from `main`. Name the branch
+   `feature/<short-description>` for additive work, `fix/<short-
+   description>` for bug fixes, `docs/<short-description>` for
+   documentation-only work. The driver sessions use
+   `feature/v<target-version>-<slug>` (e.g.
+   `feature/v0.16.0-owner-invite`) — that shape is welcome but not
+   required for outside contributors, since contributors do not
+   pick the target version.
+4. **Do not bump `VERSION` or `frontend/package.json#version` in
+   your PR.** The operator picks the target version at integration
+   time; bumping ahead causes cherry-pick conflicts. The same
+   applies to the `CHANGELOG.md` entry header — see below.
+5. **Do not tag releases, do not run any deploy gesture, do not
+   touch any deployment's `.rfc-app-version` pin.** The operator
+   alone owns those gestures. (For OHM specifically: "I'm the only
+   one that gets to yolo." See the boundary section in
+   `ohm-rfc/CONTRIBUTING.md`.)
+6. Push your branch and open a PR. Describe what you're proposing
+   and why, in language the operator can paste into the eventual
+   release commit. If the change touches `SPEC.md`, name which
+   section(s) and the contract change.
+
+---
+
+## CHANGELOG convention: strict descending
+
+`CHANGELOG.md` is ordered **newest-on-top**. The header line for
+the in-progress version goes at the top of the file; older
+releases descend below it. This is the binding convention; the
+operator hand-resolves the conflict when two parallel feature
+branches both insert at the top of the file (the squash-merge
+integration that ships parallel-feature waves keeps the strict-
+descending shape — see Session K for the cherry-pick mechanics and
+Session L for the hand-resolved-with-a-small-script variant).
+
+A new entry has this shape (read the existing 0.15.0 / 0.16.0 /
+0.17.0 entries for worked examples):
+
+```markdown
+## 0.X.Y — YYYY-MM-DD
+
+**Minor — schema migration auto-applied; no operator action.** This
+release ships <one or two sentences naming the feature and why>.
+
+### Added
+- **<New module/endpoint/component>** — what it does, where it lives,
+  why it exists. Include file paths inline so a reader can click through.
+### Changed
+- **<Existing surface>** — what changed and how a deployment notices.
+### Migration
+- **`<NNN_name>.sql`** — auto-applied by `db.run_migrations()` on
+  backend start. <Describe the schema delta in one sentence.>
+### Upgrade steps (from 0.(X-1).Y)
+- You **MUST** … (per RFC 2119; see SPEC.md §20.4).
+- You **MUST NOT** …
+- You **SHOULD** …
+- You **MAY** …
+```
+
+The header version number is filled in by the operator at merge
+time. Your PR's CHANGELOG diff can leave the version as
+`0.X.Y — YYYY-MM-DD` (literal placeholder), or use a guessed value
+the operator overwrites; either is fine.
+
+---
+
+## `Upgrade steps:` blocks use RFC 2119 keywords
+
+If your change requires deployments to do anything when they
+upgrade — set an env var, apply a migration, restart a process,
+flip an overlay value, accept a behavioral change — your CHANGELOG
+entry **must** include an `### Upgrade steps` block, and that
+block **must** use the [RFC 2119](https://www.rfc-editor.org/rfc/rfc2119)
+/ [RFC 8174](https://www.rfc-editor.org/rfc/rfc8174) keywords as
+defined in `SPEC.md` §20.4:
+
+- **MUST** / **SHALL** / **REQUIRED** — without this step the
+  deployment will not function correctly. Skipping is a regression
+  the framework does not handle.
+- **MUST NOT** / **SHALL NOT** — previously valid, now no longer
+  supported.
+- **SHOULD** / **RECOMMENDED** — the framework's tested path. A
+  deployment may deviate when it has a reason.
+- **SHOULD NOT** / **NOT RECOMMENDED** — discouraged without being
+  forbidden.
+- **MAY** / **OPTIONAL** — an affordance you can take or skip.
+
+Cross-version upgrades (jumping more than one minor) are computed by
+the operator composing each intervening release's steps in order.
+Each adjacent step must therefore be locally unambiguous — this is
+the whole reason the keyword discipline is binding. Avoid words
+like "should probably" or "might want to" inside an upgrade step;
+either the framework needs the action or it doesn't.
+
+If your change touches the env contract, **also update**
+`backend/.env.example` and/or `frontend/.env.example` in the same
+PR so the contract and the documentation land together (§20.4).
+
+---
+
+## SPEC.md and §19.2 candidates
+
+`SPEC.md` is the framework's binding spec. It is honest about open
+questions — large sections of it carry "§19.2 candidates," which
+are decisions the project has deliberately deferred rather than
+guessed at.
+
+The discipline: **architectural or process deferrals get noted as
+§19.2 candidates rather than scope-creeping a release.** When you
+notice that your change opens a question larger than the change
+itself (a different DB shape, a new auth contract, a cross-cutting
+UX rethink), the right move is usually to land the narrow change
+and add a §19.2 candidate naming the larger question. The candidate
+documents what was set aside and why, so a future session can pick
+it up with context.
+
+Worked examples from recent sessions:
+
+- v0.11.0 (Session K) shipped device trust and surfaced three new
+  §19.2 candidates: cross-device session revocation, password-
+  equivalent change invalidating trust, device-trust window
+  tunables via env. None of those were in the v0.11.0 scope; they
+  were noted in SPEC.md §19.2 so a future session can address them
+  on their own terms.
+- v0.15.0 (Session L) shipped the Amplitude wrapper and added
+  candidates around session-replay-specific consent category +
+  bundle-size measurement, both deferred to the future Part-A audit.
+
+When you spot a deferred decision in your PR's territory, name it
+in your PR description and add it to `SPEC.md` §19.2 in the same
+diff. Do not silently expand scope to settle it.
+
+---
+
+## Test-coverage expectations
+
+The backend has the load-bearing test suite at
+`backend/tests/`. Tests are organized as `*_vertical.py` files,
+each covering one feature end-to-end through the FastAPI app
+(provisioning fixtures, hitting the HTTP surface, asserting on the
+database state). At time of writing, the suite is ~250 tests across
+~25 files. Examples:
+
+- `test_admin_create_user_invite_vertical.py` — v0.17.0's
+  admin-create user + invite + claim flow, 15 tests covering happy
+  path + every refusal shape + the audit-trail row.
+- `test_rfc_invitations_vertical.py` — v0.16.0's per-RFC invite +
+  accept flow, 18 tests.
+- `test_device_trust_vertical.py` — v0.11.0's 30-day device trust,
+  14 tests including cookie shape, hash-vs-raw-token discipline,
+  expired / revoked / forged / cross-user invariants.
+
+Expected coverage for a new feature:
+
+- **Backend feature** — one new `test_<feature>_vertical.py` file
+  that covers the happy path, every documented refusal/error code,
+  and any cross-surface effect (rows the feature writes to existing
+  tables, fields it adds to existing endpoints). Reuse fixtures
+  from neighboring test files (e.g. `test_propose_vertical.py`'s
+  `FakeGitea` is widely reused).
+- **Migration** — verify migrations are reachable from `backend/.venv`
+  before pushing: `cd backend && PYTHONPATH=. .venv/bin/pytest -q`
+  exercises `db.run_migrations()` through the fixture setup.
+- **Frontend feature** — there is currently no frontend test
+  runner. The discipline is: keep the change ships-clean
+  (`cd frontend && npm run build` succeeds), and the backend
+  vertical test exercises the HTTP contract the frontend
+  consumes, which is the meaningful behavioral guarantee.
+  Frontend changes that ride along with a backend feature land
+  with the backend test as the regression boundary.
+- **Bug fix** — add a regression test in the same vertical file
+  that proves the original failure mode and verifies the fix.
+
+Run the backend suite before pushing. From `backend/`:
+
+```bash
+PYTHONPATH=. .venv/bin/pytest -q
+```
+
+(The `PYTHONPATH=.` is a known ergonomic gap — see SPEC.md §19.2
+candidate; the suite does not pick up `app/` without it.)
+
+If your PR doesn't include tests, the operator will ask for them
+before merge unless the change is genuinely test-irrelevant
+(documentation, comments, dev-only tooling).
+
+---
+
+## Analytics instrumentation checklist
+
+> *(This section codifies `ohm-rfc/ROADMAP.md` #21 Part B's
+> CONTRIBUTING checklist. It is discipline, not a gate — but the
+> operator will push back on PRs that skip it.)*
+
+If your PR adds or changes a user-facing feature, walk this
+checklist before opening the PR. The instrumentation conventions
+themselves are specified in `SPEC.md` §21 (Analytics instrumentation
+and identity); this section is the procedural reminder.
+
+1. **What named event(s) does this feature need?**
+   Open `frontend/src/lib/analytics.js` and look at the `EVENTS`
+   constant. Does an existing event cover your feature? If not, is
+   the new event in the spec's "Subject Verb" Title Case form
+   (`Comment Posted`, `Invitation Sent`)? Are the prop families
+   consistent with SPEC.md §21's required-prop catalog (opaque
+   ids only, no PII, enums lowercased like `'otc'` not `'OTC'`)?
+
+2. **Do interactive elements have stable text / ARIA labels /
+   `data-amp-track-*` so autocapture is meaningful?**
+   The frontend ships `autocapture: true`, which instruments
+   every click and form interaction. The *value* of those events
+   depends on the DOM the SDK sees: a `<button>` with stable
+   visible text or an `aria-label` shows up as a meaningful
+   dashboard row; an icon-only `<button>` with no label shows up
+   as garbage. New components that introduce interactive elements
+   should either carry meaningful labels (visible text or ARIA) or
+   carry a `data-amp-track-name="<Stable Name>"` attribute. For
+   repeated rows (per-RFC lists, comment lists), use a stable
+   `data-amp-track-*` identifier so per-row click counts aggregate
+   to the row's identity rather than to a generic label.
+
+3. **Does any new form field need replay masking?**
+   Session replay records at `sampleRate: 1` (100% of consented
+   sessions). New form inputs that capture passwords, OTC codes,
+   tokens, magic-link URLs, or other secret/credential-equivalent
+   material **MUST** be masked with Amplitude's masking conventions
+   (the `.amp-mask` class or the `data-amp-mask` attribute,
+   whichever the wrapper integration expects in this version).
+   New inputs that capture arguably-PII (email, real name, free-
+   text drafts) **SHOULD** also be masked; if a deliberate
+   un-masking decision is taken, document it in the PR description
+   and in `SPEC.md` §21.
+
+4. **Does the PR description name the instrumentation decisions?**
+   A one-sentence summary in the PR description — "fires
+   `Comment Posted` with `{rfc_slug, comment_id}`; no new form
+   fields, no new replay-masking concerns" — is enough. If the
+   decision is "we chose not to instrument this," say that too;
+   the absence of an event is itself a decision the operator
+   wants visible. The relevant SPEC chapter (§21) is the binding
+   reference for what shapes are correct.
+
+If your feature touches an identity-meaningful surface (sign-in,
+sign-out, invite-claim, role change, account state change), also
+walk the **identity lifecycle** contract in SPEC.md §21.6: every
+new claim/sign-in path **MUST** call `identify({ user_id, properties })`
+BEFORE the first `track()` event on that surface, so the Amplitude
+user record is created with the OHM user_id from the very first
+event rather than as an anonymous device that retroactively links.
+v0.16.0's `AcceptInvitation.jsx` and v0.17.0's `InviteClaim.jsx`
+are the worked examples; mirror their shape.
+
+---
+
+## The operator-only gestures
+
+Some gestures are operator-only. Contributors do not perform them;
+PRs that perform them get rejected on principle, not on merit:
+
+- **Tagging a release** (`git tag v0.X.Y` + `git push --tags`).
+- **Pushing to `main`** after merge (the operator merges; the
+  framework's `main` branch tracks releases the operator has
+  shipped).
+- **Bumping `VERSION` and `frontend/package.json#version` to the
+  shipped value.** The operator does this at integration time so
+  the version line is consistent across the release commit.
+- **Running `flotilla deploy` or any equivalent deployment gesture**
+  in any deployment of rfc-app. Contributors do not deploy.
+- **Moving a deployment's `.rfc-app-version` pin.** That pin lives
+  in the deployment's content repo (e.g. `ohm-rfc/.rfc-app-version`)
+  and is moved by the deployment's operator. Contributors to that
+  deployment do not move it; contributors to the framework
+  certainly do not.
+- **Setting secrets** (anywhere — Secret Manager, env files,
+  `flotilla secret set`, vendor dashboards, anything). The
+  binding rule baked in mid-Session-K is: **the assistant never
+  asks the operator to paste secret bytes into a conversation,
+  even as one offered option**. The corollary for contributors:
+  do not include secret values in PR descriptions, commit
+  messages, or issue comments. Reference secrets by their binding
+  name (`SMTP_PASSWORD`, `AMPLITUDE_API_KEY`) and let the
+  operator handle the bytes.
+
+If your change requires a new secret or env var, document the
+requirement in the CHANGELOG `### Upgrade steps` block in the
+RFC 2119 form ("operators **MUST** set `<NEW_VAR>` ...") and
+update the `*.env.example` file. The operator will run the
+secret/overlay-set gesture themselves at deploy time.
+
+---
+
+## When in doubt
+
+- **Open an Issue first.** Especially for any change that touches
+  SPEC.md, the auth/permissions model (§6), the storage shape (§4
+  / §5), or the deploy contract (§20). The operator (or a future
+  driver session) will name what they want before you write code.
+- **Read the most recent session transcript.** It will tell you
+  what shipped last and what's in flight.
+- **Cite SPEC.md sections in your PR description.** "Touches §15.4
+  (per-category email toggles) and adds §19.2 candidate around
+  per-channel mute granularity" gives the operator a map of where
+  to read.
+
+---
+
+## License
+
+The framework is released under the MIT License (see
+[`LICENSE`](./LICENSE)). By contributing, you agree your work
+ships under those terms.
+
+---
+
+## See also
+
+- [`SPEC.md`](./SPEC.md) — the framework's binding spec. §19.2
+  is the deferred-decisions queue; §20 is the versioning + deploy
+  contract; §21 is the analytics instrumentation contract.
+- [`CHANGELOG.md`](./CHANGELOG.md) — release history in strict
+  descending order. Read recent entries for the shape your PR's
+  release-commit will take.
+- [`PHILOSOPHY.md`](./PHILOSOPHY.md) — what the framework is for.
+  PRs whose shape conflicts with the philosophy get a longer
+  conversation than PRs that fit.
+- [`wiggleverse/ohm-session-history`](https://git.wiggleverse.org/wiggleverse/ohm-session-history)
+  — the authoritative record of how the project has actually
+  evolved, session by session.

DOCS.md

@@ -39,23 +39,44 @@ thread. Every write affordance is replaced with a sign-in prompt.
 
 ## Signing in
 
-While the framework is in private beta, only invited email addresses
-can complete sign-in. If your email is on the allowlist, the
-"Sign in" button in the header completes the flow and lands you on
-the catalog with full read and write access. If your email is not on
-the allowlist, you'll be sent to a short "pending" page explaining
-the gate.
+Anyone can start the sign-in flow with their own email address — there
+is no invite-only allowlist. Sign-in is passwordless:
 
-Once you have an account, you're a **contributor** by default — the
-role that grants every write affordance the app exposes, scoped by
-the per-RFC and per-branch rules described below.
+1. **Enter your email.** If the deployment has human verification
+   enabled (a Cloudflare Turnstile challenge), you complete it here.
+2. **Enter the one-time code.** The app emails you a short numeric
+   code; entering it signs you in. Codes expire after a few minutes,
+   and repeated wrong entries briefly lock the email.
+3. **Set a passcode (optional).** After your first code sign-in you
+   can set a passcode. On later visits you sign in with email +
+   passcode, with the one-time code as the forgot-passcode fallback.
+4. **Trust this device (optional).** You can mark a device trusted for
+   30 days to skip the code/passcode step on it. Trusted devices are
+   listed in your settings and can be revoked individually or all at
+   once.
+
+### Getting write access
+
+Signing in gives you an account, but write access is gated. The first
+time you sign in you're asked for your first name, last name, and a
+short note on why you'd like access; you then land on a "request in
+review" page. While your account is **pending**, you can read
+everything an anonymous visitor can but cannot write — no chat,
+propose, branch, PR, or discussion post. Once an admin **grants** your
+account you become a **contributor**, the role that carries every
+write affordance the app exposes, scoped by the per-RFC and per-branch
+rules described below.
+
+An admin can also create your account ahead of time and email you an
+invite link. Clicking it claims the account and signs you in with the
+role the admin assigned, skipping the one-time-code step.
 
 ---
 
 ## Proposing a new RFC
 
 A new RFC begins as a proposal. The "+ Propose new RFC" button at
-the bottom of the catalog opens a small modal that collects four
+the bottom of the catalog opens a small modal that collects five
 things:
 
 - **Title.** The word, concept, or topic this RFC would define.
@@ -65,8 +86,13 @@ things:
   inline.
 - **Pitch.** One or two paragraphs answering *why this RFC is
   needed*. This becomes the body of the entry.
-- **Tags.** Optional. The AI suggests tags from the pitch; you can
-  accept, dismiss, or type your own.
+- **Use case.** Optional. *What will you be using this RFC for?* —
+  the concrete application driving the proposal, as distinct from the
+  abstract case for it. Leaving it blank is fine.
+- **Tags.** Optional. If the deployment has AI tag suggestion
+  enabled, suggested tags appear as you fill the form (with an inline
+  note that the text you've entered is sent to the model that
+  generates them); you can accept, dismiss, or type your own.
 
 Submitting the modal does one concrete thing: it opens a pull
 request against the framework's meta repository, adding one new
@@ -167,6 +193,51 @@ either requires a contributor account.
 
 ---
 
+## Invitations, cross-references, and contribution requests
+
+Three connected surfaces help the right people find and join the
+right RFC.
+
+### Owner invitations
+
+An RFC's owner (or an app-wide admin or owner) can invite a specific
+person to that RFC from the "Invitations" control in the RFC header.
+The invite names an email and a role for *this RFC*:
+
+- **contributor** — can open PRs and join the discussion;
+- **discussant** — can join the discussion only.
+
+The invitee gets an email with an accept link; accepting adds them as
+a collaborator on that RFC. The invitations panel lists every invite
+with its status (pending / accepted / expired / revoked); pending
+invites can be revoked. An invitation is per-RFC — it does not change
+the invitee's app-wide role, and it cannot lift the pending gate: the
+invitee still needs a granted account to write.
+
+### RFC cross-links in PRs and comments
+
+When a PR description or a comment mentions an existing active RFC —
+by its ID, its multi-word title, or its slug — the framework renders
+that mention as a link to the RFC. The matching is conservative by
+design (single common words are never auto-linked), and the links are
+computed at read time, so nothing is rewritten in what you typed.
+
+### "Create" and "ask to contribute" offers
+
+The same scan surfaces two affordances inline:
+
+- If a term looks like it should have an RFC but none exists yet, a
+  reader who has create rights sees a **"create RFC for '<term>'"**
+  link that opens the propose modal with the title pre-filled.
+- If a term matches a *pending* RFC (a super-draft someone already
+  owns), a signed-in reader sees an **"ask to contribute"** offer
+  naming the owner. It opens a short request form — who you are, why
+  you're asking, and optionally what you'd use the RFC for. The
+  request lands in the owner's inbox; the owner can **accept** (which
+  sends you an owner invitation) or **decline** (which notifies you).
+
+---
+
 ## Working on a branch
 
 Contribute mode flips one branch into edit-enabled. The centre
@@ -505,6 +576,14 @@ Each role is a strict superset of the one below it.
    entirely. The framework names a single "owner zero" at
    bootstrap.
 
+Between anonymous and contributor sits one transient state:
+**pending**. A freshly signed-in account that hasn't been granted
+access yet (see [Signing in](#signing-in)) reads everything an
+anonymous visitor can, but no write affordance unlocks until an admin
+grants it. Granting promotes the account to contributor; an admin can
+also revoke a granted account back to a no-write state. These
+transitions are recorded in the `permission_events` log.
+
 The practical difference between admin and owner is narrow but
 load-bearing: admin is the operational tier — it does the day-to-
 day moderation and stewardship work; owner is the tier that
@@ -594,6 +673,20 @@ review.
 
 ---
 
+## Privacy and cookies
+
+A consent banner appears on your first visit and lets you choose
+which cookie categories to allow — essential always, with analytics
+and other categories opt-in. The choice is remembered and can be
+changed any time from the privacy/cookies controls in settings.
+
+Analytics only load if you opt in: the framework defers the analytics
+SDK behind your consent, so declining means it is never initialized.
+The `/privacy` and `/cookies` pages describe what's collected and
+why; a deployment can point those pages at its own fuller policy.
+
+---
+
 ## Where to learn more
 
 - The framework's *why* lives in [the philosophy

Dockerfile

@@ -0,0 +1,62 @@
+# rfc-app container image — the Cloud Run keystone for per-PR preview
+# environments (flotilla SPEC §15). NOT used by production: prod still deploys
+# via the pin-based on-VM gesture (flotilla §8). This image exists so flotilla
+# `preview up --pr=N` can build a PR's tree and run it as an ephemeral,
+# scale-to-zero Cloud Run service with a SEEDED SYNTHETIC database and ZERO real
+# secrets (test-secret env only — flotilla §15 / §3 invariant 1).
+#
+# Single container, single port: nginx serves the built SPA on $PORT (Cloud Run
+# injects it) and reverse-proxies /api/ + /auth/ to a single-process uvicorn on
+# 127.0.0.1:8000 — mirroring the prod nginx + systemd split
+# (deploy/nginx/ohm.wiggleverse.org.conf, deploy/systemd/rfc-app.service), so a
+# preview behaves like prod minus the secrets. Single uvicorn process + single
+# SQLite file, per §4.2 (never scale workers).
+#
+# Build context is the repo root:  docker build -t <image> .
+
+# ---- stage 1: build the Vite SPA -------------------------------------------
+FROM node:20-slim AS web
+WORKDIR /app/frontend
+COPY frontend/package.json frontend/package-lock.json ./
+RUN npm ci
+COPY frontend/ ./
+# VITE_* values are baked into the bundle at build time (intentionally public —
+# §8 phase-5 note). VITE_APP_NAME is REQUIRED by vite.config.js (the framework
+# ships no default — each deployment names itself); previews self-name. Turnstile
+# uses Cloudflare's always-pass test SITE key so the widget renders + auto-passes.
+ARG VITE_APP_NAME="RFC App (preview)"
+ARG VITE_TURNSTILE_SITE_KEY=1x00000000000000000000AA
+ARG VITE_AMPLITUDE_API_KEY=
+RUN VITE_APP_NAME="$VITE_APP_NAME" \
+    VITE_TURNSTILE_SITE_KEY="$VITE_TURNSTILE_SITE_KEY" \
+    VITE_AMPLITUDE_API_KEY="$VITE_AMPLITUDE_API_KEY" \
+    npm run build
+
+# ---- stage 2: runtime (backend + nginx) ------------------------------------
+FROM python:3.12-slim AS runtime
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends nginx gettext-base sqlite3 \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /opt/rfc-app
+
+# Backend deps first for layer caching.
+COPY backend/requirements.txt backend/requirements.txt
+RUN pip install --no-cache-dir -r backend/requirements.txt
+
+COPY backend/ backend/
+COPY deploy/preview/ deploy/preview/
+# health.py reads VERSION at parents[2] (== /opt/rfc-app/VERSION).
+COPY VERSION ./
+COPY --from=web /app/frontend/dist/ frontend/dist/
+
+RUN chmod +x deploy/preview/entrypoint.sh
+
+# Cloud Run injects $PORT (default 8080); the entrypoint renders nginx against
+# it. The synthetic preview DB lives on the container's ephemeral filesystem and
+# dies with the instance (zero create/seed/drop lifecycle — §15).
+ENV PORT=8080 \
+    DATABASE_PATH=/opt/rfc-app/backend/data/rfc-app.db
+EXPOSE 8080
+
+ENTRYPOINT ["deploy/preview/entrypoint.sh"]

Makefile

@@ -0,0 +1,19 @@
+.PHONY: tier1-up tier1-down tier1-logs fe-unit e2e e2e-install
+
+tier1-up:
+	docker compose -f testing/docker-compose.yml up --build -d
+
+tier1-down:
+	docker compose -f testing/docker-compose.yml down -v
+
+tier1-logs:
+	docker compose -f testing/docker-compose.yml logs -f
+
+fe-unit:
+	cd frontend && npm run test:run
+
+e2e-install:
+	cd e2e && npm ci && npx playwright install chromium
+
+e2e:
+	cd e2e && BASE_URL=$${BASE_URL:-http://localhost:8080} MAILSINK_URL=$${MAILSINK_URL:-http://localhost:8025} npm run e2e

VERSION

@@ -1 +1 @@
-0.9.0
+0.42.0

backend/.env.example

@@ -9,10 +9,18 @@ GITEA_URL=http://localhost:3000
 GITEA_BOT_USER=rfc-bot
 GITEA_BOT_TOKEN=
 
-# The Gitea org or user that owns the meta repo and every RFC repo
-# the bot will create on graduation.
+# The Gitea org or user that owns every RFC repo the bot will create on
+# graduation.
 GITEA_ORG=wiggleverse
-META_REPO=meta
+
+# §22.2 — the project registry repo (REQUIRED). The framework reads
+# `projects.yaml` at its root to learn which projects exist. The repo name is
+# the deployment's choice; the app fails to start if this is unset.
+REGISTRY_REPO=registry
+# §22.13 — optional id for the bootstrap/default project. Reserved for the
+# Plan B re-stamp; leave unset in Plan A (the default project id stays
+# `default`). When set, it must match an `id` in projects.yaml.
+# DEFAULT_PROJECT_ID=ohm
 
 # --- OAuth (Gitea) ---
 # In Gitea: Site Administration → Applications → Add OAuth2 Application.
@@ -38,10 +46,22 @@ GITEA_WEBHOOK_SECRET=change-me-to-a-shared-secret
 # Comma-separated list of provider keys to enable. Per the §19.2
 # per-RFC-model topic, this is app-wide until that topic lands.
 ENABLED_MODELS=claude
+# ANTHROPIC_API_KEY also powers the §9.1 propose-RFC tag suggestions
+# (roadmap #27) — that surface always uses Claude Haiku for cost,
+# independent of ENABLED_MODELS. With no key set, tag suggestions are
+# simply unavailable (the modal hides the row); the rest of the app is
+# unaffected.
 ANTHROPIC_API_KEY=
 GOOGLE_API_KEY=
 OPENAI_API_KEY=
 
+# --- Tag suggestions (§9.1 / roadmap #27) ---
+# Per-user rate limit on the suggest-tags endpoint (cost backstop; the
+# modal debounces and the endpoint is contributor-gated). Optional —
+# these defaults apply when unset.
+TAG_SUGGEST_RATE_MAX=30
+TAG_SUGGEST_RATE_WINDOW_SECONDS=60
+
 # --- Email (§15.4) ---
 # Leave SMTP_HOST unset to use the stdout fallback — the integration
 # tests rely on it, and a dev environment without a real SMTP provider
@@ -92,3 +112,21 @@ OTC_TTL_MINUTES=10
 # loud-failure shape so the abuse path is visible). Set to 0 to
 # disable the cooldown — useful for tests but never in production.
 OTC_REQUEST_COOLDOWN_SECONDS=60
+
+# --- v0.12.0: CloudFlare Turnstile gate on OTC dispatch (§6.2, item #10) ---
+# Provision a Turnstile site at dash.cloudflare.com → Turnstile → Add
+# site. The site key (public) goes in `frontend/.env` as
+# VITE_TURNSTILE_SITE_KEY. The secret key (private) goes here and is
+# what the backend POSTs to /siteverify alongside the user's response
+# token. Leave both unset for dev/test paths; the gate stays open when
+# the secret is absent AND TURNSTILE_REQUIRED=false (the default).
+CLOUDFLARE_TURNSTILE_SECRET=
+
+# When `true`, /auth/otc/request fails closed (HTTP 500 "auth
+# misconfigured") if CLOUDFLARE_TURNSTILE_SECRET is unset. When `false`
+# (the default), a missing secret skips verification — useful in dev
+# and during the pre-rollout window when the operator hasn't wired
+# the secret yet. Flip to `true` once the secret is wired so a future
+# config drift surfaces as a loud 500 rather than a silent abuse-
+# defense disablement.
+TURNSTILE_REQUIRED=false

backend/app/api.py

@@ -15,18 +15,28 @@ import json
 from typing import Any
 
 from fastapi import APIRouter, HTTPException, Request
+from fastapi.responses import PlainTextResponse, Response
 from pydantic import BaseModel, Field
 
 from . import (
     api_admin,
     api_branches,
+    api_collections,
+    api_contributions,
+    api_deployment,
     api_discussion,
     api_graduation,
+    api_invitations,
     api_notifications,
     api_prs,
     auth,
+    collections as collections_mod,
+    projects as projects_mod,
     db,
+    device_trust as device_trust_mod,
     docs as docs_mod,
+    docs_sessions,
+    docs_specs,
     entry as entry_mod,
     cache,
     funder,
@@ -34,6 +44,7 @@ from . import (
     notify,
     philosophy,
     providers as providers_mod,
+    tag_suggest,
 )
 from .bot import Bot
 from .config import Config
@@ -46,6 +57,22 @@ class ProposeBody(BaseModel):
     slug: str = Field(min_length=1, max_length=80)
     pitch: str = Field(min_length=1)
     tags: list[str] = Field(default_factory=list)
+    # Roadmap #26: optional "What will you be using this RFC for?" — the
+    # concrete ground-truth use case, distinct from the `pitch`'s abstract
+    # "why is this needed." Optional (NULL/omitted accepted), no minimum,
+    # generous cap matching the pitch's free-text body bound.
+    proposed_use_case: str | None = Field(default=None, max_length=8000)
+
+
+class SuggestTagsBody(BaseModel):
+    # Roadmap #27: the partial propose-RFC draft, sent as the user types
+    # (debounced on the frontend). All fields optional — suggestions
+    # refine as the draft fills in. `pitch` is the "why is this needed"
+    # rationale; `use_case` is the #26 optional ground-truth field.
+    # Bounds mirror the propose body's free-text caps.
+    title: str = Field(default="", max_length=200)
+    pitch: str = Field(default="", max_length=8000)
+    use_case: str = Field(default="", max_length=8000)
 
 
 class DeclineBody(BaseModel):
@@ -57,6 +84,18 @@ class FunderCredentialBody(BaseModel):
     api_key: str = Field(min_length=1, max_length=2048)
 
 
+class LastStateBody(BaseModel):
+    # v0.23.0 / roadmap item #29: server-side sign-in state resume.
+    # `route` is a frontend pathname the user was last on (bounded so a
+    # hostile client can't stuff arbitrary blobs through). `state` is an
+    # optional bag of *light* view state (scroll anchors, open tab,
+    # filter chips). PRIVACY: it MUST NOT carry draft-buffer contents —
+    # the frontend only ever sends ephemeral view state, and the column
+    # comment in migration 022 + SPEC §6.2 are the binding contract.
+    route: str = Field(min_length=1, max_length=2048)
+    state: dict[str, Any] | None = None
+
+
 class BetaRequestBody(BaseModel):
     # v0.8.0 — captured on the first OTC sign-in. All three fields are
     # required so the admin queue has a coherent triage shape.
@@ -101,6 +140,20 @@ def make_router(
     # Contribution still requires a PR (api_prs above); this surface
     # is for discussion that does not yet warrant a branch.
     router.include_router(api_discussion.make_router())
+    # v0.16.0 (roadmap item #12): owner-only invite for per-RFC
+    # contribution + discussion. The RFC's owner can invite specific
+    # users by email to either open PRs or join the discussion; non-
+    # invited users keep read access but cannot write (v0.6.0
+    # contract extended to per-RFC scope).
+    router.include_router(api_invitations.make_router())
+    # v0.29.0 (roadmap item #28 Part 3): offer-to-contribute-to-a-pending
+    # (super-draft) RFC. Reuses the #12 invite flow (api_invitations above)
+    # on accept; lands the request + owner notifications via §15 notify.
+    router.include_router(api_contributions.make_router())
+    # §22.9/§22.10 (M3): runtime deployment + per-project config (replaces
+    # VITE_APP_NAME) + the old-URL 308 redirects.
+    router.include_router(api_deployment.make_router(config))
+    router.include_router(api_collections.make_router(config, gitea, bot))
 
     # ---------------------------------------------------------------
     # §17: /api/health — unauthenticated post-flight probe.
@@ -135,6 +188,177 @@ def make_router(
         payload = docs_mod.load()
         return {"body": payload["body"]}
 
+    # ---------------------------------------------------------------
+    # v0.19.0 / roadmap item #30 — /api/docs/sessions/*
+    #
+    # The framework mediates reads against the public
+    # `wiggleverse/ohm-session-history` gitea repo so the rendered
+    # `/docs/sessions/*` surface inherits the same chrome as the
+    # /docs/user-guide route and doesn't require a cross-origin
+    # gesture from the frontend. See backend/app/docs_sessions.py
+    # for the cache shape and env knobs.
+    #
+    # The route mapping for the three `status` values returned by
+    # the fetchers:
+    #
+    #   "ok"     → HTTP 200, payload as documented per endpoint
+    #   "404"    → HTTP 200/404 depending on the endpoint (the
+    #              manifest's empty state is 200 + {} so the
+    #              frontend can short-circuit without an error
+    #              banner; transcripts/about return 404 so the
+    #              frontend can render its own empty-state)
+    #   "error"  → HTTP 502, {"error": ..., "detail": ...} so the
+    #              frontend retry surface reads as "couldn't reach
+    #              the session-history repo" rather than as a
+    #              generic 5xx.
+    # ---------------------------------------------------------------
+
+    @router.get("/api/docs/sessions/manifest")
+    async def get_sessions_manifest() -> dict[str, Any]:
+        result = await docs_sessions.fetch_manifest()
+        if result["status"] == "ok":
+            return result["manifest"]
+        if result["status"] == "404":
+            # Empty-state contract: render no session rows in the
+            # flyout but don't show an error banner. The frontend
+            # treats `{}` as "no sessions published yet".
+            return {}
+        raise HTTPException(
+            status_code=502,
+            detail={
+                "error": "session-history fetch failed",
+                "detail": result.get("detail", "unknown"),
+            },
+        )
+
+    @router.get("/api/docs/sessions/about")
+    async def get_sessions_about() -> Response:
+        result = await docs_sessions.fetch_about()
+        if result["status"] == "ok":
+            return PlainTextResponse(
+                content=result["body"],
+                media_type="text/markdown; charset=utf-8",
+            )
+        if result["status"] == "404":
+            raise HTTPException(
+                status_code=404,
+                detail="session-history README not yet published",
+            )
+        raise HTTPException(
+            status_code=502,
+            detail={
+                "error": "session-history fetch failed",
+                "detail": result.get("detail", "unknown"),
+            },
+        )
+
+    @router.get("/api/docs/sessions/{nnnn}/index")
+    async def get_sessions_index(nnnn: str) -> dict[str, Any]:
+        if not docs_sessions._is_valid_session_dir(nnnn):
+            # 400 over 404: the request itself is malformed (the
+            # session directory name doesn't match `^\d{4}$`),
+            # distinct from "no such session published yet".
+            raise HTTPException(status_code=400, detail="invalid session directory")
+        result = await docs_sessions.fetch_session_index(nnnn)
+        if result["status"] == "ok":
+            return {"files": result["files"]}
+        if result["status"] == "404":
+            raise HTTPException(
+                status_code=404,
+                detail="no transcripts published for this session",
+            )
+        raise HTTPException(
+            status_code=502,
+            detail={
+                "error": "session-history fetch failed",
+                "detail": result.get("detail", "unknown"),
+            },
+        )
+
+    @router.get("/api/docs/sessions/{nnnn}/{filename}")
+    async def get_sessions_transcript(nnnn: str, filename: str) -> Response:
+        # Path-shape validation before any network — refuses anything
+        # that would resolve outside the `NNNN/SESSION-...md` layout
+        # (e.g. legacy `SESSION-A-TRANSCRIPT.md` at the repo root,
+        # `../etc/passwd`, or any non-numeric session dir).
+        if not docs_sessions._is_valid_session_dir(nnnn):
+            raise HTTPException(status_code=400, detail="invalid session directory")
+        if not docs_sessions._is_valid_transcript_filename(filename):
+            raise HTTPException(status_code=400, detail="invalid transcript filename")
+        result = await docs_sessions.fetch_transcript(nnnn, filename)
+        if result["status"] == "ok":
+            return PlainTextResponse(
+                content=result["body"],
+                media_type="text/markdown; charset=utf-8",
+            )
+        if result["status"] == "404":
+            raise HTTPException(
+                status_code=404,
+                detail="transcript not found",
+            )
+        raise HTTPException(
+            status_code=502,
+            detail={
+                "error": "session-history fetch failed",
+                "detail": result.get("detail", "unknown"),
+            },
+        )
+
+    # ---------------------------------------------------------------
+    # v0.20.0 — /api/docs/specs/*
+    #
+    # Sibling of the v0.19.0 docs-sessions surface: the framework
+    # mediates a fetch against the public gitea raw URL for each
+    # configured spec so the rendered `/docs/specs/*` route inherits
+    # the same chrome (and the same auth-less reach) as the user
+    # guide and the session-history browser. See
+    # backend/app/docs_specs.py for the manifest shape, the env
+    # knobs, and the cache.
+    #
+    # Status-to-HTTP mapping mirrors docs_sessions:
+    #   "ok"    → HTTP 200, payload as documented per endpoint
+    #   "404"   → HTTP 200 / 404 (manifest 404 doesn't apply here —
+    #             the manifest is derived from env, never 404s; spec
+    #             404 returns HTTP 404 so the frontend can render
+    #             "spec not yet published / unknown name")
+    #   "error" → HTTP 502
+    # ---------------------------------------------------------------
+
+    @router.get("/api/docs/specs/manifest")
+    async def get_specs_manifest() -> dict[str, Any]:
+        # The manifest is derived from env (`OHM_DOCS_SPECS`) and
+        # never fails — a malformed value falls back to the framework
+        # default at parse time. So this endpoint always returns 200
+        # + a list (the framework default is non-empty).
+        result = docs_specs.fetch_specs_manifest()
+        return {"specs": result["specs"]}
+
+    @router.get("/api/docs/specs/{name}")
+    async def get_spec(name: str) -> Response:
+        # Slug validation before any network — refuses `..`, `/`,
+        # uppercase, whitespace, etc. Same defense-in-depth posture
+        # as the docs-sessions transcript endpoint.
+        if not docs_specs._is_valid_name(name):
+            raise HTTPException(status_code=400, detail="invalid spec name")
+        result = await docs_specs.fetch_spec(name)
+        if result["status"] == "ok":
+            return PlainTextResponse(
+                content=result["body"],
+                media_type="text/markdown; charset=utf-8",
+            )
+        if result["status"] == "404":
+            raise HTTPException(
+                status_code=404,
+                detail="spec not found",
+            )
+        raise HTTPException(
+            status_code=502,
+            detail={
+                "error": "specs fetch failed",
+                "detail": result.get("detail", "unknown"),
+            },
+        )
+
     # ---------------------------------------------------------------
     # Auth surface — reads role from our users table per §6.
     # ---------------------------------------------------------------
@@ -167,6 +391,28 @@ def make_router(
         )
         has_passcode = bool(row and row["passcode_hash"])
         passcode_set_at = row["passcode_set_at"] if (row and has_passcode) else None
+        # v0.23.0 / item #29: fold the sign-in-resume state onto the
+        # same round-trip the frontend already makes on boot. When
+        # resume is disabled (resume_enabled = 0) we hand back a null
+        # route so the client never redirects; the stored row stays put
+        # so re-enabling later resumes the last-known route.
+        state_row = db.conn().execute(
+            "SELECT last_route, last_route_state, resume_enabled "
+            "FROM user_session_state WHERE user_id = ?",
+            (user.user_id,),
+        ).fetchone()
+        resume_enabled = bool(state_row["resume_enabled"]) if state_row else True
+        last_route = (
+            state_row["last_route"]
+            if (state_row and resume_enabled)
+            else None
+        )
+        last_route_state = None
+        if state_row and resume_enabled and state_row["last_route_state"]:
+            try:
+                last_route_state = json.loads(state_row["last_route_state"])
+            except (ValueError, TypeError):
+                last_route_state = None
         return {
             "authenticated": True,
             "user": {
@@ -183,6 +429,10 @@ def make_router(
                 "needs_profile": needs_profile,
                 "has_passcode": has_passcode,
                 "passcode_set_at": passcode_set_at,
+                # v0.23.0 / item #29 — sign-in state resume.
+                "resume_enabled": resume_enabled,
+                "last_route": last_route,
+                "last_route_state": last_route_state,
             },
         }
 
@@ -252,30 +502,153 @@ def make_router(
             notify.fan_out_new_beta_request(requester_user_id=user.user_id)
         return {"ok": True}
 
+    # ---------------------------------------------------------------
+    # v0.23.0 (§6.2, roadmap item #29): server-side sign-in state
+    # resume. The frontend debounce-posts the user's current route +
+    # a small bag of light view state here on every route change; the
+    # next sign-in reads `last_route` off `/api/auth/me` and redirects.
+    #
+    # Per-user (NOT per-device) — one row per user, keyed on user_id.
+    # `resume_enabled` is the opt-out flag (default on); when it's 0
+    # this endpoint no-ops so a user who turned resume off doesn't keep
+    # silently rewriting their stored route. PRIVACY: the body carries
+    # route + light state ONLY, never draft-buffer contents (migration
+    # 022 column comment + SPEC §6.2 are the binding contract).
+    #
+    # `require_user` (not `require_contributor`) — a pending/granted
+    # distinction is irrelevant for "remember where I was", and a
+    # pending user navigating read-only surfaces should still resume.
+    # Anonymous callers get the 401 `require_user` raises.
+    # ---------------------------------------------------------------
+
+    @router.put("/api/me/last-state")
+    async def put_last_state(body: LastStateBody, request: Request) -> dict[str, Any]:
+        user = auth.require_user(request)
+        # Respect the opt-out: if a row already exists with resume
+        # disabled, leave it untouched and report the no-op. A first-
+        # ever POST (no row yet) defaults to enabled and stores.
+        existing = db.conn().execute(
+            "SELECT resume_enabled FROM user_session_state WHERE user_id = ?",
+            (user.user_id,),
+        ).fetchone()
+        if existing is not None and not existing["resume_enabled"]:
+            return {"ok": True, "stored": False}
+        state_json = json.dumps(body.state) if body.state is not None else None
+        db.conn().execute(
+            """
+            INSERT INTO user_session_state
+                (user_id, last_route, last_route_state, last_updated_at)
+            VALUES (?, ?, ?, datetime('now'))
+            ON CONFLICT(user_id) DO UPDATE SET
+                last_route = excluded.last_route,
+                last_route_state = excluded.last_route_state,
+                last_updated_at = excluded.last_updated_at
+            """,
+            (user.user_id, body.route, state_json),
+        )
+        return {"ok": True, "stored": True}
+
+    # ---------------------------------------------------------------
+    # v0.11.0: trust device for 30 days (§6.2, roadmap item #9).
+    #
+    # The mint path lives on the OAuth router (issuing the cookie is
+    # coupled to OTC/passcode verify). This module owns the read/revoke
+    # surface the /settings/devices page calls.
+    # ---------------------------------------------------------------
+
+    @router.get("/api/auth/me/devices")
+    async def list_my_devices(request: Request) -> dict[str, Any]:
+        """Active device-trust rows for the signed-in user.
+
+        Active = not revoked, not expired. The current request's
+        device (if any) is *not* singled out here — the surface
+        shows the same row shape for every device so the user can
+        revoke any of them without the page leaking which row
+        carries the cookie they're using right now.
+        """
+        user = auth.require_user(request)
+        rows = device_trust_mod.list_for_user(user.user_id)
+        return {
+            "items": [
+                {
+                    "id": r.id,
+                    "created_at": r.created_at,
+                    "expires_at": r.expires_at,
+                    "last_seen_at": r.last_seen_at,
+                    "user_agent": r.user_agent,
+                }
+                for r in rows
+            ]
+        }
+
+    @router.delete("/api/auth/me/devices/{device_id}")
+    async def revoke_my_device(device_id: int, request: Request) -> dict[str, Any]:
+        """Revoke a single device-trust row for the signed-in user.
+
+        The user-id scope is enforced in SQL so a hostile client
+        cannot revoke another user's row by guessing ids. A row that
+        doesn't exist, doesn't belong to this user, or is already
+        revoked reads as 404 — the wrong-vs-already-revoked
+        distinction would only help a probing client enumerate ids.
+        """
+        user = auth.require_user(request)
+        ok = device_trust_mod.revoke(user.user_id, device_id)
+        if not ok:
+            raise HTTPException(404, "Device not found")
+        return {"ok": True}
+
+    @router.delete("/api/auth/me/devices")
+    async def revoke_all_my_devices(request: Request) -> dict[str, Any]:
+        """Revoke every active device-trust row for the signed-in user.
+
+        The user's current request stays authenticated via its
+        session cookie; the device-trust cookie carried on the
+        current device is also revoked, but `rfc_session` keeps the
+        request flow alive until sign-out / expiry.
+        """
+        user = auth.require_user(request)
+        count = device_trust_mod.revoke_all(user.user_id)
+        return {"ok": True, "revoked": count}
+
     # ---------------------------------------------------------------
     # §7: the catalog
     # ---------------------------------------------------------------
 
     @router.get("/api/rfcs")
-    async def list_rfcs(request: Request) -> dict[str, Any]:
+    async def list_rfcs(request: Request, unreviewed: str | None = None) -> dict[str, Any]:
         """§7's left pane data.
 
         The chip-filter / sort / search combinatorics live on the
         client — the server returns the full set and lets the chips
         narrow it. The set is small (hundreds, not thousands) for the
         foreseeable future, so paginating here would buy nothing.
+
+        §22.4c: pass `?unreviewed=true` to narrow to active entries
+        still awaiting owner review.
         """
         viewer = auth.current_user(request)
         viewer_id = viewer.user_id if viewer else None
+        # §22.5: a gated project's entries never surface in a non-member's
+        # catalog. For the single public default project this is the full set.
+        visible = auth.visible_project_ids(viewer)
+        if not visible:
+            return {"items": []}
+        placeholders = ",".join("?" for _ in visible)
+        params = list(visible)
+        unreviewed_clause = ""
+        if unreviewed is not None and unreviewed.lower() in ("1", "true", "yes"):
+            unreviewed_clause = " AND unreviewed = 1 AND state = 'active'"
         rows = db.conn().execute(
-            """
-            SELECT slug, title, state, rfc_id, repo,
-                   owners_json, arbiters_json, tags_json,
-                   last_main_commit_at, last_entry_commit_at, updated_at
-              FROM cached_rfcs
-             WHERE state IN ('super-draft', 'active')
-             ORDER BY COALESCE(last_main_commit_at, last_entry_commit_at) DESC
-            """
+            f"""
+            SELECT r.slug, r.title, r.state, r.rfc_id, r.repo,
+                   r.owners_json, r.arbiters_json, r.tags_json,
+                   r.last_main_commit_at, r.last_entry_commit_at, r.updated_at
+              FROM cached_rfcs r JOIN collections c ON c.id = r.collection_id
+             WHERE r.state IN ('super-draft', 'active')
+               AND c.project_id IN ({placeholders}){unreviewed_clause}
+             ORDER BY COALESCE(r.last_main_commit_at, r.last_entry_commit_at) DESC
+            """,
+            params,
         ).fetchall()
 
         starred = set()
@@ -307,27 +680,227 @@ def make_router(
         return {"items": items}
 
     @router.get("/api/rfcs/{slug}")
-    async def get_rfc(slug: str) -> dict[str, Any]:
+    async def get_rfc(slug: str, request: Request) -> dict[str, Any]:
         row = db.conn().execute(
             "SELECT * FROM cached_rfcs WHERE slug = ?", (slug,)
         ).fetchone()
         if row is None:
             raise HTTPException(404, "Not found")
-        return _serialize_rfc(row)
+        viewer = auth.current_user(request)
+        # §22.5 visibility gate (subtractive, §22.7): a gated project's entries
+        # 404 to non-members. Recover the project via the entry's collection.
+        auth.require_project_readable(viewer, auth.project_of_rfc(slug))
+        # §13.7: a retired entry is removed from every browsing surface. The
+        # sole exception is a site owner, so the un-retire affordance has
+        # somewhere to live; everyone else gets a plain 404.
+        if row["state"] == "retired" and (viewer is None or viewer.role != "owner"):
+            raise HTTPException(404, "Not found")
+        payload = _serialize_rfc(row)
+        # Roadmap #26: surface the optional propose-time use case on the
+        # RFC view. The idea PR closes on merge, but the canonical row in
+        # `proposed_use_cases` persists; look it up by slug (the latest
+        # 'rfc'-scope row for this slug). NULL == "left blank".
+        uc = db.conn().execute(
+            """
+            SELECT use_case FROM proposed_use_cases
+             WHERE scope = 'rfc' AND rfc_slug = ?
+             ORDER BY id DESC LIMIT 1
+            """,
+            (slug,),
+        ).fetchone()
+        payload["proposed_use_case"] = uc["use_case"] if uc else None
+        return payload
+
+    # ---------------------------------------------------------------
+    # §22.4 (Plan B): per-project RFC serving — the catalog + entry view
+    # scoped to one project, identified by its own slug namespace
+    # (project_id, slug). The unscoped /api/rfcs[/{slug}] above stay as the
+    # default-project compat path; the frontend reads these scoped routes so a
+    # second project's corpus renders under /p/<id>/.
+    # ---------------------------------------------------------------
+
+    def _require_collection_in_project(collection_id: str, project_id: str) -> None:
+        # §22 S2: a collection-scoped route 404s when the collection does not
+        # belong to the project in the path (shape matches an unknown id).
+        if collections_mod.project_of_collection(collection_id) != project_id:
+            raise HTTPException(404, "Not found")
+
+    def _list_rfcs_for_collection(
+        collection_id: str, viewer, unreviewed: str | None
+    ) -> dict[str, Any]:
+        viewer_id = viewer.user_id if viewer else None
+        unreviewed_clause = ""
+        if unreviewed is not None and unreviewed.lower() in ("1", "true", "yes"):
+            unreviewed_clause = " AND unreviewed = 1 AND state = 'active'"
+        rows = db.conn().execute(
+            f"""
+            SELECT slug, title, state, rfc_id, repo,
+                   owners_json, arbiters_json, tags_json,
+                   last_main_commit_at, last_entry_commit_at, updated_at
+              FROM cached_rfcs
+             WHERE state IN ('super-draft', 'active')
+               AND collection_id = ?{unreviewed_clause}
+             ORDER BY COALESCE(last_main_commit_at, last_entry_commit_at) DESC
+            """,
+            (collection_id,),
+        ).fetchall()
+        starred = set()
+        if viewer_id is not None:
+            starred = {
+                r["rfc_slug"]
+                for r in db.conn().execute(
+                    "SELECT rfc_slug FROM stars WHERE user_id = ? AND collection_id = ?",
+                    (viewer_id, collection_id),
+                )
+            }
+        items = [
+            {
+                "slug": r["slug"],
+                "title": r["title"],
+                "state": r["state"],
+                "id": r["rfc_id"],
+                "repo": r["repo"],
+                "owners": json.loads(r["owners_json"] or "[]"),
+                "arbiters": json.loads(r["arbiters_json"] or "[]"),
+                "tags": json.loads(r["tags_json"] or "[]"),
+                "last_active_at": r["last_main_commit_at"] or r["last_entry_commit_at"] or r["updated_at"],
+                "starred_by_me": r["slug"] in starred,
+                "has_open_prs": False,
+            }
+            for r in rows
+        ]
+        return {"items": items}
+
+    def _get_rfc_for_collection(collection_id: str, slug: str, viewer) -> dict[str, Any]:
+        row = db.conn().execute(
+            "SELECT * FROM cached_rfcs WHERE collection_id = ? AND slug = ?",
+            (collection_id, slug),
+        ).fetchone()
+        if row is None:
+            raise HTTPException(404, "Not found")
+        if row["state"] == "retired" and (viewer is None or viewer.role != "owner"):
+            raise HTTPException(404, "Not found")
+        payload = _serialize_rfc(row)
+        uc = db.conn().execute(
+            """
+            SELECT use_case FROM proposed_use_cases
+             WHERE scope = 'rfc' AND rfc_slug = ? AND collection_id = ?
+             ORDER BY id DESC LIMIT 1
+            """,
+            (slug, collection_id),
+        ).fetchone()
+        payload["proposed_use_case"] = uc["use_case"] if uc else None
+        return payload
+
+    @router.get("/api/projects/{project_id}/rfcs")
+    async def list_project_rfcs(
+        project_id: str, request: Request, unreviewed: str | None = None
+    ) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        # §22.5 read gate: a gated project's catalog 404s to a non-member.
+        auth.require_project_readable(viewer, project_id)
+        # §22 S1: the project-scoped route serves the default collection.
+        collection_id = collections_mod.default_collection_id(project_id)
+        return _list_rfcs_for_collection(collection_id, viewer, unreviewed)
+
+    @router.get("/api/projects/{project_id}/rfcs/{slug}")
+    async def get_project_rfc(project_id: str, slug: str, request: Request) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        auth.require_project_readable(viewer, project_id)
+        collection_id = collections_mod.default_collection_id(project_id)
+        return _get_rfc_for_collection(collection_id, slug, viewer)
+
+    # §22 S2: collection-scoped serve + propose. The catalog/entry views read
+    # these under /p/<project>/c/<collection>/; the project-scoped routes above
+    # stay as the default-collection compat surface.
+    @router.get("/api/projects/{project_id}/collections/{collection_id}/rfcs")
+    async def list_collection_rfcs(
+        project_id: str, collection_id: str, request: Request,
+        unreviewed: str | None = None,
+    ) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        auth.require_project_readable(viewer, project_id)
+        _require_collection_in_project(collection_id, project_id)
+        # §22.5 (S3): a hidden/gated collection 404s to a non-scope-role viewer.
+        auth.require_collection_readable(viewer, collection_id)
+        return _list_rfcs_for_collection(collection_id, viewer, unreviewed)
+
+    @router.get("/api/projects/{project_id}/collections/{collection_id}/rfcs/{slug}")
+    async def get_collection_rfc(
+        project_id: str, collection_id: str, slug: str, request: Request
+    ) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        auth.require_project_readable(viewer, project_id)
+        _require_collection_in_project(collection_id, project_id)
+        auth.require_collection_readable(viewer, collection_id)
+        return _get_rfc_for_collection(collection_id, slug, viewer)
+
+    # ---------------------------------------------------------------
+    # §22.4c: mark-reviewed — clear an active entry's `unreviewed` flag
+    # ---------------------------------------------------------------
+
+    @router.post("/api/projects/{project_id}/rfcs/{slug}/mark-reviewed")
+    async def mark_reviewed(project_id: str, slug: str, request: Request) -> dict[str, Any]:
+        """§22.4c — clear an active entry's `unreviewed` flag. Authority is the
+        §B.2 collection Owner (a collection/project/global Owner or deployment
+        owner/admin reaching the entry's collection)."""
+        viewer = auth.require_user(request)
+        auth.require_project_readable(viewer, project_id)
+        collection_id = collections_mod.default_collection_id(project_id)
+        if not auth.is_collection_superuser(viewer, collection_id):
+            raise HTTPException(403, "Only a collection owner can mark an entry reviewed")
+        row = db.conn().execute(
+            "SELECT state, unreviewed FROM cached_rfcs WHERE slug = ? AND collection_id = ?",
+            (slug, collection_id),
+        ).fetchone()
+        if row is None:
+            raise HTTPException(404, "Not found")
+        if row["state"] != "active" or not row["unreviewed"]:
+            raise HTTPException(409, "Entry is not an unreviewed active entry")
+        try:
+            await bot.mark_entry_reviewed(
+                viewer.as_actor(),
+                org=config.gitea_org,
+                meta_repo=(projects_mod.default_content_repo(config) or ""),
+                slug=slug,
+                reviewed_by=viewer.gitea_login,
+                reviewed_at=entry_mod.today(),
+            )
+        except GiteaError as e:
+            raise HTTPException(502, f"Gitea: {e.detail}")
+        await cache.refresh_meta_repo(config, gitea)
+        return {"ok": True}
 
     # ---------------------------------------------------------------
     # §7.3 / §9.3: pending ideas
     # ---------------------------------------------------------------
 
+    def _proposal_use_case(pr_number: int) -> str | None:
+        """Roadmap #26: read the optional use case for an idea PR from the
+        canonical side table. Returns None when none was supplied (the
+        "left blank" sentinel the frontend renders tastefully)."""
+        row = db.conn().execute(
+            "SELECT use_case FROM proposed_use_cases WHERE scope = 'rfc' AND pr_number = ?",
+            (pr_number,),
+        ).fetchone()
+        return row["use_case"] if row else None
+
     @router.get("/api/proposals")
-    async def list_proposals() -> dict[str, Any]:
+    async def list_proposals(request: Request) -> dict[str, Any]:
+        # §22.5: idea PRs in a gated project never surface to non-members.
+        visible = auth.visible_project_ids(auth.current_user(request))
+        if not visible:
+            return {"items": []}
+        placeholders = ",".join("?" for _ in visible)
         rows = db.conn().execute(
-            """
+            f"""
             SELECT rfc_slug, pr_number, title, description, opened_by, opened_at, state
               FROM cached_prs
              WHERE pr_kind = 'idea' AND state = 'open'
+               AND project_id IN ({placeholders})
              ORDER BY opened_at DESC
-            """
+            """,
+            visible,
         ).fetchall()
         return {
             "items": [
@@ -338,6 +911,36 @@ def make_router(
                     "description": r["description"],
                     "opened_by": r["opened_by"],
                     "opened_at": r["opened_at"],
+                    "proposed_use_case": _proposal_use_case(r["pr_number"]),
+                }
+                for r in rows
+            ]
+        }
+
+    @router.get("/api/projects/{project_id}/proposals")
+    async def list_project_proposals(project_id: str, request: Request) -> dict[str, Any]:
+        # §22.4/§22.5: the pending idea-PRs scoped to one project.
+        viewer = auth.current_user(request)
+        auth.require_project_readable(viewer, project_id)
+        rows = db.conn().execute(
+            """
+            SELECT rfc_slug, pr_number, title, description, opened_by, opened_at, state
+              FROM cached_prs
+             WHERE pr_kind = 'idea' AND state = 'open' AND project_id = ?
+             ORDER BY opened_at DESC
+            """,
+            (project_id,),
+        ).fetchall()
+        return {
+            "items": [
+                {
+                    "slug": r["rfc_slug"],
+                    "pr_number": r["pr_number"],
+                    "title": r["title"],
+                    "description": r["description"],
+                    "opened_by": r["opened_by"],
+                    "opened_at": r["opened_at"],
+                    "proposed_use_case": _proposal_use_case(r["pr_number"]),
                 }
                 for r in rows
             ]
@@ -361,10 +964,12 @@ def make_router(
         ).fetchone()
         if row is None:
             raise HTTPException(404, "Not a proposal PR")
+        # §22.5 visibility gate (subtractive): gated → 404 to non-members.
+        auth.require_project_readable(auth.current_user(request), row["project_id"])
         # Read the proposed entry file from the head branch.
         slug = row["rfc_slug"]
         head = row["head_branch"]
-        result = await gitea.read_file(config.gitea_org, config.meta_repo, f"rfcs/{slug}.md", ref=head)
+        result = await gitea.read_file(config.gitea_org, (projects_mod.default_content_repo(config) or ""), f"rfcs/{slug}.md", ref=head)
         entry_payload: dict[str, Any] | None = None
         if result:
             text, _sha = result
@@ -386,15 +991,28 @@ def make_router(
             "opened_at": row["opened_at"],
             "entry": entry_payload,
             "affordances": affordances,
+            "proposed_use_case": _proposal_use_case(pr_number),
         }
 
     # ---------------------------------------------------------------
     # §9.1: propose a new RFC
     # ---------------------------------------------------------------
 
-    @router.post("/api/rfcs/propose")
-    async def propose_rfc(payload: ProposeBody, request: Request) -> dict[str, Any]:
-        user = auth.require_contributor(request)
+    async def _propose_into_project(project_id: str, payload: ProposeBody, user) -> dict[str, Any]:
+        # Default-collection wrapper (§22 S1/S2): resolve the project's default
+        # collection and delegate. Keeps the project-scoped propose routes intact.
+        return await _propose_into_collection(
+            project_id, collections_mod.default_collection_id(project_id), payload, user
+        )
+
+    async def _propose_into_collection(
+        project_id: str, collection_id: str, payload: ProposeBody, user
+    ) -> dict[str, Any]:
+        # §B.2 (S3): proposing a new entry requires contribute standing in the
+        # *target collection* — the four-layer scope-role union, with the
+        # grandfathered implicit-public baseline on the default collection.
+        if not auth.can_contribute_in_collection(user, collection_id):
+            raise HTTPException(403, "You do not have contribute access to this collection")
         slug = payload.slug.strip().lower()
         if not entry_mod.is_valid_slug(slug):
             raise HTTPException(422, "Slug must be lowercase letters, digits, and dashes")
@@ -404,21 +1022,29 @@ def make_router(
         # on every keystroke, since a concurrent submission could land
         # between dialog-open and submit.
         clash = db.conn().execute(
-            "SELECT 1 FROM cached_rfcs WHERE slug = ?", (slug,)
+            "SELECT 1 FROM cached_rfcs WHERE slug = ? AND collection_id = ?", (slug, collection_id)
         ).fetchone()
         if clash:
             raise HTTPException(409, f"Slug `{slug}` is already taken")
         idea_clash = db.conn().execute(
-            "SELECT 1 FROM cached_prs WHERE pr_kind = 'idea' AND state = 'open' AND rfc_slug = ?",
-            (slug,),
+            "SELECT 1 FROM cached_prs WHERE pr_kind = 'idea' AND state = 'open' "
+            "AND rfc_slug = ? AND project_id = ?",
+            (slug, project_id),
         ).fetchone()
         if idea_clash:
             raise HTTPException(409, f"Slug `{slug}` is already reserved by an open proposal")
 
+        # §22.4b: the target collection's landing state (the per-corpus field
+        # moved down to the collection in migration 029).
+        landing_state = (
+            "active" if collections_mod.collection_initial_state(collection_id) == "active"
+            else "super-draft"
+        )
+
         entry = entry_mod.Entry(
             slug=slug,
             title=payload.title.strip(),
-            state="super-draft",
+            state=landing_state,
             id=None,
             repo=None,
             proposed_by=user.email or user.gitea_login,
@@ -433,6 +1059,7 @@ def make_router(
             arbiters=[],
             tags=[t.strip() for t in payload.tags if t.strip()],
             body=payload.pitch.strip() + "\n",
+            unreviewed=(landing_state == "active"),
         )
         contents = entry_mod.serialize(entry)
         pr_title = f"Propose: {entry.title}"
@@ -443,15 +1070,19 @@ def make_router(
             f"**Topic:** {entry.title}\n\n"
             f"{payload.pitch.strip()}"
         )
+        # §22 S2: write the entry under the target collection's <subfolder>/rfcs.
+        subfolder = collections_mod.subfolder_of(collection_id)
+        rfcs_dir = f"{subfolder}/rfcs" if subfolder else "rfcs"
         try:
             pr = await bot.open_idea_pr(
                 user.as_actor(),
                 org=config.gitea_org,
-                meta_repo=config.meta_repo,
+                meta_repo=(projects_mod.content_repo(project_id) or ""),
                 slug=slug,
                 file_contents=contents,
                 pr_title=pr_title,
                 pr_description=pr_description,
+                rfcs_dir=rfcs_dir,
             )
         except GiteaError as e:
             raise HTTPException(502, f"Gitea: {e.detail}")
@@ -462,8 +1093,84 @@ def make_router(
         # cache write is idempotent.)
         await cache.refresh_meta_pulls(config, gitea)
 
+        # Roadmap #26: persist the optional use case to the canonical,
+        # reconcile-proof side table keyed by the idea PR number. NULL/
+        # blank simply writes no row (absence == "left blank"). Done after
+        # the refresh so the cache row exists; the mirror onto cached_prs
+        # keeps the cache column in parity for any read that uses it.
+        use_case = (payload.proposed_use_case or "").strip()
+        if use_case:
+            db.conn().execute(
+                """
+                INSERT INTO proposed_use_cases (scope, rfc_slug, pr_number, use_case, collection_id)
+                VALUES ('rfc', ?, ?, ?, ?)
+                ON CONFLICT(collection_id, scope, pr_number) DO UPDATE SET use_case = excluded.use_case
+                """,
+                (slug, pr["number"], use_case, collection_id),
+            )
+            db.conn().execute(
+                "UPDATE cached_prs SET proposed_use_case = ? WHERE pr_kind = 'idea' AND pr_number = ? AND project_id = ?",
+                (use_case, pr["number"], project_id),
+            )
+
         return {"pr_number": pr["number"], "slug": slug}
 
+    @router.post("/api/rfcs/propose")
+    async def propose_rfc(payload: ProposeBody, request: Request) -> dict[str, Any]:
+        # Default-project compat path (pre-multi-project clients).
+        user = auth.require_contributor(request)
+        return await _propose_into_project(projects_mod.resolved_default_id(config), payload, user)
+
+    @router.post("/api/projects/{project_id}/rfcs/propose")
+    async def propose_project_rfc(
+        project_id: str, payload: ProposeBody, request: Request
+    ) -> dict[str, Any]:
+        # §22.4: propose a new entry into a specific project (read-gated first
+        # so a gated project 404s a non-member before the contribute check).
+        user = auth.require_contributor(request)
+        auth.require_project_readable(user, project_id)
+        return await _propose_into_project(project_id, payload, user)
+
+    @router.post("/api/projects/{project_id}/collections/{collection_id}/rfcs/propose")
+    async def propose_collection_rfc(
+        project_id: str, collection_id: str, payload: ProposeBody, request: Request
+    ) -> dict[str, Any]:
+        # §22 S2: propose a new entry into a specific collection of a project.
+        user = auth.require_contributor(request)
+        auth.require_project_readable(user, project_id)
+        _require_collection_in_project(collection_id, project_id)
+        # §22.5 (S3): a hidden/gated collection 404s a non-scope-role viewer
+        # before the contribute check (existence is not revealed).
+        auth.require_collection_readable(user, collection_id)
+        return await _propose_into_collection(project_id, collection_id, payload, user)
+
+    # ---------------------------------------------------------------
+    # §9.1 Slice 2 (roadmap #27): Claude Haiku tag suggestions as the
+    # propose-RFC fields fill in. The modal debounce-posts the partial
+    # draft; we constrain Haiku to the corpus's existing tag set and
+    # return a short ranked list of clickable chips. Gated to
+    # contributors (same gate as propose) so the cost surface is bounded
+    # to people who can actually file an RFC; rate-limited per user as a
+    # backstop. Degrades to an empty list (no error) when no Anthropic
+    # key is bound, the corpus has no tags yet, or the draft is empty —
+    # so the modal simply shows nothing extra.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/suggest-tags")
+    async def suggest_rfc_tags(payload: SuggestTagsBody, request: Request) -> dict[str, Any]:
+        user = auth.require_contributor(request)
+        if not tag_suggest.rate_limit_ok(user.user_id):
+            raise HTTPException(429, "Too many tag-suggestion requests; please slow down.")
+        provider = tag_suggest.haiku_provider(config)
+        if provider is None:
+            return {"suggestions": []}
+        universe = tag_suggest.gather_tag_universe()
+        draft = tag_suggest.Draft(
+            title=payload.title, pitch=payload.pitch, use_case=payload.use_case
+        )
+        suggestions = tag_suggest.suggest(provider, draft, universe)
+        return {"suggestions": suggestions}
+
     # ---------------------------------------------------------------
     # §9.3: merge / decline / withdraw an idea PR
     # ---------------------------------------------------------------
@@ -476,7 +1183,7 @@ def make_router(
             await bot.merge_idea_pr(
                 user.as_actor(),
                 org=config.gitea_org,
-                meta_repo=config.meta_repo,
+                meta_repo=(projects_mod.default_content_repo(config) or ""),
                 pr_number=pr_number,
                 slug=row["rfc_slug"],
             )
@@ -496,7 +1203,7 @@ def make_router(
             await bot.decline_idea_pr(
                 user.as_actor(),
                 org=config.gitea_org,
-                meta_repo=config.meta_repo,
+                meta_repo=(projects_mod.default_content_repo(config) or ""),
                 pr_number=pr_number,
                 slug=row["rfc_slug"],
                 comment=body.comment,
@@ -520,7 +1227,7 @@ def make_router(
             await bot.withdraw_idea_pr(
                 user.as_actor(),
                 org=config.gitea_org,
-                meta_repo=config.meta_repo,
+                meta_repo=(projects_mod.default_content_repo(config) or ""),
                 pr_number=pr_number,
                 slug=row["rfc_slug"],
             )
@@ -576,6 +1283,8 @@ def make_router(
         ).fetchone()
         if rfc is None:
             raise HTTPException(404, "RFC not found")
+        # §22.5 visibility gate (subtractive): gated → 404 to non-members.
+        auth.require_project_readable(user, auth.project_of_rfc(slug))
         # §6.7: refuse consent from a user with no registered credentials
         # — a consent without a universe would be inert and the surface
         # should fail loudly rather than silently.

backend/app/api_admin.py

@@ -11,6 +11,8 @@ The endpoints in this module:
   - `GET  /api/admin/users`                       — list users with role + mute
   - `POST /api/admin/users/<id>/role`             — set role per §6.1
   - `POST /api/admin/users/<id>/mute`             — set the §6.2 write-mute
+  - `POST /api/admin/users`                       — v0.17.0: create user + invite
+  - `GET  /api/admin/users/invites`               — v0.17.0: pending invites
   - `GET  /api/admin/audit`                       — paged `actions` log
   - `GET  /api/admin/permission-events`           — paged `permission_events` log
   - `GET  /api/admin/graduation-queue`            — super-drafts ready to graduate
@@ -33,8 +35,9 @@ from typing import Any
 from fastapi import APIRouter, HTTPException, Query, Request
 from pydantic import BaseModel, Field
 
-from . import auth, db
+from . import auth, db, email_invite, invites
 from .config import Config
+from .email import EmailConfig
 
 
 # ---------------------------------------------------------------------------
@@ -65,6 +68,32 @@ class AllowlistAddBody(BaseModel):
     note: str | None = Field(default=None, max_length=200)
 
 
+class CreateUserInviteBody(BaseModel):
+    """v0.17.0 / roadmap item #16 — admin-create user + invite email.
+
+    The admin types these fields on the "Create user + invite" modal on
+    `/admin/users`. The email + role are required; first/last name and
+    the optional custom message round out the body.
+
+    Bounds mirror the rest of the codebase:
+      * `email`: 320 chars — RFC 5321 envelope limit, same as
+        `OtcRequestBody` / `BetaRequestBody` / `AllowlistAddBody`.
+      * `first_name` / `last_name`: 120 chars — same as the v0.8.0
+        `BetaRequestBody` capture form.
+      * `role`: pydantic regex pinned to the §6.1 set so an unknown
+        role fails at the body bound (422) instead of landing as a
+        CHECK constraint violation in the migration.
+      * `custom_message`: 500 chars — the brief calls this out as
+        the max. The frontend modal shows a "remaining chars"
+        counter to match.
+    """
+    email: str = Field(min_length=3, max_length=320)
+    first_name: str = Field(default="", max_length=120)
+    last_name: str = Field(default="", max_length=120)
+    role: str = Field(pattern="^(owner|admin|contributor)$")
+    custom_message: str = Field(default="", max_length=500)
+
+
 # ---------------------------------------------------------------------------
 # Router
 # ---------------------------------------------------------------------------
@@ -90,6 +119,17 @@ def make_router(config: Config) -> APIRouter:
 
         `permission_decided_by_login` joins the deciding admin row so
         the UI can render "granted by @ben" without a second round-trip.
+
+        v0.16.0 (roadmap item #12) additive: each user row now carries
+        an `rfc_invitations` array — the per-RFC invitations the user
+        has accepted. This is the "permission-grant requests from
+        invited users" hook the roadmap text calls for: when a user
+        accepts a per-RFC invite and they're not yet platform-granted,
+        the admin sees "here because @ben invited them to <RFC> as
+        <role>" alongside their pending row, informing (not deciding)
+        the platform grant. The two write surfaces remain distinct —
+        the RFC's owner controls per-RFC roles; the admin controls
+        platform-grant state.
         """
         auth.require_admin(request)
         rows = db.conn().execute(
@@ -115,6 +155,62 @@ def make_router(config: Config) -> APIRouter:
                 u.display_name COLLATE NOCASE
             """
         ).fetchall()
+        # v0.16.0 — per-user accepted per-RFC invitations. One query
+        # over the full set, indexed bucket-by-user-id in Python so
+        # the per-row attachment below is O(1). Empty array for users
+        # who hold no accepted invitations.
+        invitation_rows = db.conn().execute(
+            """
+            SELECT c.user_id, c.rfc_slug, c.role_in_rfc, c.created_at,
+                   r.title AS rfc_title,
+                   i.id AS invitation_id, i.invitee_email,
+                   ui.gitea_login AS inviter_login,
+                   ui.display_name AS inviter_display
+              FROM rfc_collaborators c
+         LEFT JOIN cached_rfcs r ON r.slug = c.rfc_slug
+         LEFT JOIN rfc_invitations i ON i.id = c.invitation_id
+         LEFT JOIN users ui ON ui.id = i.inviter_user_id
+             ORDER BY c.created_at DESC
+            """
+        ).fetchall()
+        per_user_invites: dict[int, list[dict]] = {}
+        for ir in invitation_rows:
+            per_user_invites.setdefault(ir["user_id"], []).append({
+                "rfc_slug": ir["rfc_slug"],
+                "rfc_title": ir["rfc_title"] or ir["rfc_slug"],
+                "role_in_rfc": ir["role_in_rfc"],
+                "invited_at": ir["created_at"],
+                "invitation_id": ir["invitation_id"],
+                "invitee_email": ir["invitee_email"],
+                "inviter_login": ir["inviter_login"],
+                "inviter_display": ir["inviter_display"],
+            })
+        # v0.17.0 / roadmap item #16: a user row whose `last_seen_at`
+        # is NULL is one of two things — a brand-new row that was just
+        # provisioned (rare, and the v0.7.0 OTC verify path stamps
+        # last_seen_at on the same call that creates the row), or an
+        # admin-created invite-pending row (v0.17.0 — created by
+        # `POST /api/admin/users`). We surface a `pending_invite_id`
+        # field by joining through `user_invite_tokens` so the
+        # Users tab can render a "(pending invite)" badge alongside
+        # the role/state controls. Filters to invites that are
+        # neither expired nor claimed — once the invitee clicks
+        # through, the badge clears (and `last_seen_at` populates).
+        pending_invite_rows = db.conn().execute(
+            """
+            SELECT invited_user_id, id AS invite_id, expires_at
+              FROM user_invite_tokens
+             WHERE claimed_at IS NULL
+               AND datetime(expires_at) > datetime('now')
+            """
+        ).fetchall()
+        pending_invites = {
+            r["invited_user_id"]: {
+                "invite_id": r["invite_id"],
+                "expires_at": r["expires_at"],
+            }
+            for r in pending_invite_rows
+        }
         return {
             "items": [
                 {
@@ -133,6 +229,217 @@ def make_router(config: Config) -> APIRouter:
                     "permission_decided_at": r["permission_decided_at"],
                     "permission_decided_by_login": r["decided_by_login"],
                     "permission_decided_by_display": r["decided_by_display"],
+                    # v0.16.0 additive — never null, always an array.
+                    "rfc_invitations": per_user_invites.get(r["id"], []),
+                    # v0.17.0: present iff the row is invited-but-not-
+                    # claimed-yet. The frontend renders a "(pending
+                    # invite)" badge when this is non-null.
+                    "pending_invite": pending_invites.get(r["id"]),
+                }
+                for r in rows
+            ]
+        }
+
+    # ----- Create user + invite (v0.17.0 / roadmap item #16) -----
+
+    @router.post("/api/admin/users")
+    async def create_user_with_invite(
+        body: CreateUserInviteBody, request: Request,
+    ) -> dict[str, Any]:
+        """Provision a fresh `users` row with a pre-assigned role + send
+        an invite email carrying a claim link.
+
+        Refusals:
+          * `422` — the admin tries to invite their own email (no
+            self-invite; symmetric to `set_permission`'s self-flip
+            refusal and `set_role`'s self-downgrade refusal). Use
+            the existing role-change channel for self-edits.
+          * `422` — the admin tries to grant `owner` without being
+            owner themselves. §6.1: owner-zero is the only owner
+            bootstrap path; new owners come from a sitting owner's
+            hand. A 422 here matches the message shape; a 403 would
+            also be defensible, but staying with 422 keeps the
+            "your input is bad" framing.
+          * `409` — the email already maps to a `users` row. The
+            admin should use the existing role / grant gestures on
+            the existing user, not create a duplicate.
+          * `422` — pydantic-level: malformed email, role outside
+            the §6.1 set, custom_message over 500 chars.
+
+        On success:
+          1. The invitee `users` row lands with the chosen role and
+             `permission_state='granted'` (admin's hand is the grant)
+             and `last_seen_at IS NULL` (the "(pending invite)"
+             discriminator the listing surface joins through).
+          2. The `user_invite_tokens` row lands with the bcrypt-
+             hashed opaque token; the raw token rides only in the
+             email link.
+          3. The invite email dispatches with subject "You're
+             invited to <app> by <admin>" and the custom message
+             embedded in a clearly-delimited block if present.
+          4. A `permission_events` row records the admin-create
+             gesture so the §6.5 / `permissions` admin tab carries
+             the audit trail alongside the existing grant/revoke
+             flips.
+        """
+        viewer = auth.require_admin(request)
+        email_clean = body.email.strip().lower()
+        if "@" not in email_clean or len(email_clean.split("@")[-1]) < 2:
+            raise HTTPException(422, "Email looks malformed")
+
+        # Self-invite refusal. Compare the admin's own email
+        # case-insensitively against the invite target.
+        viewer_row = db.conn().execute(
+            "SELECT email FROM users WHERE id = ?", (viewer.user_id,)
+        ).fetchone()
+        viewer_email = (viewer_row["email"] or "").strip().lower() if viewer_row else ""
+        if viewer_email and viewer_email == email_clean:
+            raise HTTPException(
+                422,
+                "You cannot invite yourself — use the role-change channel "
+                "if you need to edit your own row",
+            )
+
+        # Owner-grant refusal: §6.1 says only a sitting owner can mint
+        # a new owner. An admin trying to invite-as-owner is refused
+        # at 422; the admin should ask the owner to issue the invite,
+        # or invite as `admin` and let the owner promote later.
+        if body.role == "owner" and viewer.role != "owner":
+            raise HTTPException(
+                422,
+                "Only an owner can invite a new owner — invite as admin and "
+                "ask the owner to promote, or have the owner issue this invite",
+            )
+
+        # Duplicate-email refusal. A pre-existing row (regardless of
+        # permission_state) means the admin should use the existing
+        # role / grant gestures, not create a parallel user.
+        existing = db.conn().execute(
+            "SELECT id FROM users WHERE email = ? COLLATE NOCASE LIMIT 1",
+            (email_clean,),
+        ).fetchone()
+        if existing is not None:
+            raise HTTPException(409, "A user with this email already exists")
+
+        # Create the invitee row + token row + send the email.
+        outcome = invites.create_invite(
+            email=email_clean,
+            first_name=body.first_name,
+            last_name=body.last_name,
+            role=body.role,
+            custom_message=body.custom_message,
+            created_by_admin_id=viewer.user_id,
+        )
+
+        # Audit row in permission_events so the admin Permissions tab
+        # carries the gesture. The before-state is "n/a" (the row
+        # did not exist); the after-state is the granted role. We
+        # use a new `event_kind='user_invited'` so the existing
+        # grant/revoke kinds stay scoped to their flip surface.
+        db.conn().execute(
+            """
+            INSERT INTO permission_events
+                (actor_user_id, subject_user_id, event_kind, details)
+            VALUES (?, ?, 'user_invited', ?)
+            """,
+            (
+                viewer.user_id,
+                outcome.invited_user_id,
+                json.dumps({
+                    "email": email_clean,
+                    "role": body.role,
+                    "invite_id": outcome.invite_id,
+                    "custom_message_chars": len(body.custom_message or ""),
+                }),
+            ),
+        )
+
+        # Build the claim URL using the same APP_URL the email module
+        # reads. The token rides as a query-string param to the
+        # frontend route `/invites/claim?token=…`; the frontend POSTs
+        # it back to `/api/invites/claim` which consumes the row.
+        cfg = EmailConfig.from_env()
+        from urllib.parse import urlencode
+        claim_url = f"{cfg.app_url}/invites/claim?{urlencode({'token': outcome.raw_token})}"
+
+        # Fetch the inviter display so the email body can render
+        # "Ben Stull (ben@example.com) has invited you to …". We
+        # read off the row fresh rather than trusting the session
+        # cookie's cached display_name.
+        inviter_row = db.conn().execute(
+            "SELECT display_name, email FROM users WHERE id = ?",
+            (viewer.user_id,),
+        ).fetchone()
+        inviter_display = (
+            (inviter_row["display_name"] if inviter_row else "") or viewer.display_name or "An admin"
+        )
+        inviter_email_for_body = (inviter_row["email"] if inviter_row else "") or viewer.email or ""
+
+        email_invite.send_invite_email(
+            to_address=email_clean,
+            claim_url=claim_url,
+            inviter_display=inviter_display,
+            inviter_email=inviter_email_for_body,
+            custom_message=body.custom_message,
+        )
+
+        return {
+            "ok": True,
+            "invite_id": outcome.invite_id,
+            "invited_user_id": outcome.invited_user_id,
+            "email": email_clean,
+            "role": body.role,
+        }
+
+    @router.get("/api/admin/users/invites")
+    async def list_user_invites(request: Request) -> dict[str, Any]:
+        """List active (not claimed, not expired) admin-issued invites.
+
+        Powers the admin's "I sent these but they haven't been claimed
+        yet" view. The frontend uses this alongside `list_users` —
+        the user-listing's `pending_invite` field carries the per-row
+        flag; this endpoint carries the full invite shape for a
+        dedicated drill-in surface.
+        """
+        auth.require_admin(request)
+        rows = invites.list_pending_invites()
+        # Join through to the admin display names so the surface can
+        # render "invited by @ben" without a second client call.
+        admin_ids = {r.created_by_admin_id for r in rows}
+        admin_lookup: dict[int, dict[str, str]] = {}
+        if admin_ids:
+            placeholders = ",".join("?" * len(admin_ids))
+            admin_rows = db.conn().execute(
+                f"SELECT id, gitea_login, display_name FROM users "
+                f"WHERE id IN ({placeholders})",
+                tuple(admin_ids),
+            ).fetchall()
+            admin_lookup = {
+                ar["id"]: {
+                    "gitea_login": ar["gitea_login"] or "",
+                    "display_name": ar["display_name"] or "",
+                }
+                for ar in admin_rows
+            }
+        return {
+            "items": [
+                {
+                    "id": r.id,
+                    "email": r.email,
+                    "role": r.role,
+                    "first_name": r.first_name,
+                    "last_name": r.last_name,
+                    "custom_message": r.custom_message,
+                    "created_at": r.created_at,
+                    "expires_at": r.expires_at,
+                    "invited_user_id": r.invited_user_id,
+                    "created_by_admin_id": r.created_by_admin_id,
+                    "created_by_login": admin_lookup.get(
+                        r.created_by_admin_id, {}
+                    ).get("gitea_login", ""),
+                    "created_by_display": admin_lookup.get(
+                        r.created_by_admin_id, {}
+                    ).get("display_name", ""),
                 }
                 for r in rows
             ]
@@ -365,6 +672,73 @@ def make_router(config: Config) -> APIRouter:
             "has_more": len(rows) == limit,
         }
 
+    @router.get("/api/admin/outbound-emails")
+    async def list_outbound_emails(
+        request: Request,
+        kind: str | None = None,
+        status: str | None = None,
+        to_address: str | None = None,
+        limit: int = Query(default=100, ge=1, le=500),
+        before_id: int | None = None,
+    ) -> dict[str, Any]:
+        """v0.18.0 Slice 4: read-only inspection of the
+        `outbound_emails` audit table.
+
+        Answers questions like "did this person ever get their
+        invite?" without grepping VM logs. Filterable by kind
+        ('otc' | 'invite' | 'notification' | 'bundle' | 'digest'),
+        status ('sent' | 'failed' | 'deferred' | 'bounced'), and
+        to_address; the latter is exact-match because the audit
+        question is usually "the specific person who said they
+        didn't receive it." Per the proposal, no admin UI ships
+        with v0.18.0 — operator queries via curl + jq for now.
+        """
+        auth.require_admin(request)
+        clauses: list[str] = []
+        args: list[Any] = []
+        if kind:
+            clauses.append("kind = ?")
+            args.append(kind)
+        if status:
+            clauses.append("status = ?")
+            args.append(status)
+        if to_address:
+            clauses.append("LOWER(to_address) = LOWER(?)")
+            args.append(to_address)
+        if before_id is not None:
+            clauses.append("id < ?")
+            args.append(before_id)
+        where = ("WHERE " + " AND ".join(clauses)) if clauses else ""
+        rows = db.conn().execute(
+            f"""
+            SELECT id, to_address, from_address, subject, kind, sent_at,
+                   status, error, notification_id, message_id
+              FROM outbound_emails
+             {where}
+             ORDER BY id DESC
+             LIMIT ?
+            """,
+            (*args, limit),
+        ).fetchall()
+        return {
+            "items": [
+                {
+                    "id": r["id"],
+                    "to_address": r["to_address"],
+                    "from_address": r["from_address"],
+                    "subject": r["subject"],
+                    "kind": r["kind"],
+                    "sent_at": r["sent_at"],
+                    "status": r["status"],
+                    "error": r["error"],
+                    "notification_id": r["notification_id"],
+                    "message_id": r["message_id"],
+                }
+                for r in rows
+            ],
+            "has_more": len(rows) == limit,
+        }
+
     @router.get("/api/admin/permission-events")
     async def list_permission_events(
         request: Request,
@@ -455,6 +829,57 @@ def make_router(config: Config) -> APIRouter:
                 items_blocked.append(payload)
         return {"ready": items_ready, "blocked": items_blocked}
 
+    # ----- §13.7: retired (soft-deleted) entries — site owners only -----
+
+    @router.get("/api/admin/retired-rfcs")
+    async def retired_rfcs(request: Request) -> dict[str, Any]:
+        # Retired entries are hidden from every browsing surface (§13.7);
+        # this owner-gated list is how a site owner discovers them to
+        # un-retire. Admins do not get this surface — un-retire authority is
+        # site-owner-only, so neither is the list that feeds it.
+        viewer = auth.require_admin(request)
+        if viewer.role != "owner":
+            raise HTTPException(403, "Site owner role required")
+        rows = db.conn().execute(
+            """
+            SELECT slug, title, rfc_id, owners_json, tags_json,
+                   proposed_at, updated_at
+              FROM cached_rfcs
+             WHERE state = 'retired'
+             ORDER BY updated_at DESC
+            """
+        ).fetchall()
+        items = []
+        for r in rows:
+            # The state it would return to on un-retire, mirroring
+            # api_graduation._prior_state_before_retire's audit lookup.
+            prior = db.conn().execute(
+                """
+                SELECT details FROM actions
+                 WHERE rfc_slug = ? AND action_kind = 'retire'
+                 ORDER BY id DESC LIMIT 1
+                """,
+                (r["slug"],),
+            ).fetchone()
+            restored_state = None
+            if prior and prior["details"]:
+                try:
+                    restored_state = json.loads(prior["details"]).get("prior_state")
+                except (ValueError, TypeError):
+                    restored_state = None
+            if restored_state not in ("super-draft", "active"):
+                restored_state = "active" if r["rfc_id"] else "super-draft"
+            items.append({
+                "slug": r["slug"],
+                "title": r["title"],
+                "id": r["rfc_id"],
+                "owners": json.loads(r["owners_json"] or "[]"),
+                "tags": json.loads(r["tags_json"] or "[]"),
+                "retired_at": r["updated_at"],
+                "restores_to": restored_state,
+            })
+        return {"items": items}
+
     # ----- User search (typeahead for §15.8 mute add) -----
 
     @router.get("/api/users/search")

backend/app/api_branches.py

@@ -29,7 +29,7 @@ from fastapi import APIRouter, HTTPException, Request
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel, Field
 
-from . import auth, cache, chat as chat_layer, db, entry as entry_mod, funder, models_resolver
+from . import auth, cache, chat as chat_layer, db, entry as entry_mod, funder, models_resolver, projects as projects_mod
 from .bot import Bot
 from .config import Config
 from .gitea import Gitea, GiteaError
@@ -120,7 +120,9 @@ def make_router(
     # -------------------------------------------------------------------
 
     @router.get("/api/rfcs/{slug}/models")
-    async def list_models_for_rfc(slug: str) -> dict[str, Any]:
+    async def list_models_for_rfc(slug: str, request: Request) -> dict[str, Any]:
+        # §22.5 visibility gate (subtractive): gated → 404 to non-members.
+        _require_rfc(slug, auth.current_user(request))
         resolved = models_resolver.resolve_models_for_rfc(slug, providers)
         return {
             "models": [
@@ -140,7 +142,7 @@ def make_router(
     @router.get("/api/rfcs/{slug}/main")
     async def get_rfc_main(slug: str, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        rfc = _require_rfc(slug)
+        rfc = _require_rfc(slug, viewer)
         if rfc["state"] not in ("active", "super-draft"):
             raise HTTPException(409, f"RFC is {rfc['state']}")
 
@@ -150,7 +152,7 @@ def make_router(
         # `refresh_meta_branches` writes is internal scaffolding for the
         # §10.1 has-commits-ahead check — the §9.4 dropdown's first
         # position is rendered separately as 'canonical body'.
-        if _is_super_draft(rfc):
+        if _is_meta_resident(rfc):
             branch_rows = db.conn().execute(
                 """
                 SELECT branch_name, head_sha, state, last_commit_at, pinned
@@ -180,7 +182,7 @@ def make_router(
         # per-RFC repo. For super-draft: meta_body_edit and meta_metadata
         # PRs on the meta repo. Same shape either way — the §9.4 dropdown
         # treats both as "open work against this entry."
-        pr_kinds = ("meta_body_edit", "meta_metadata") if _is_super_draft(rfc) else ("rfc_branch",)
+        pr_kinds = ("meta_body_edit", "meta_metadata") if _is_meta_resident(rfc) else ("rfc_branch",)
         placeholders = ",".join("?" * len(pr_kinds))
         pr_rows = db.conn().execute(
             f"""
@@ -204,17 +206,18 @@ def make_router(
             for r in pr_rows
         ]
 
-        # For super-drafts the cached body is entry.body already (see
-        # cache._upsert_cached_rfc), so no extraction is needed.
-        # §9.8 / §13.4 pre-graduation history: for active RFCs, surface
-        # any `threads` or `changes` rows whose `branch_name` starts with
-        # `edit-<slug>-` so the breadcrumb dropdown can render the
-        # affordance as a distinct disclosure alongside main, open
-        # branches, and open PRs. The slug is the canonical key per §2.3
-        # before and after graduation, so the query is a straightforward
-        # lookup — no data movement.
+        # For meta-resident entries the cached body is entry.body already
+        # (see cache._upsert_cached_rfc), so no extraction is needed.
+        # Pre-graduation history is a LEGACY-only affordance: under the
+        # meta-only topology (§1, §13.4) graduation moves nothing, so an
+        # active RFC's edit branches are its *current* branches and already
+        # surface in `branches` above — there is no separate pre-graduation
+        # set. The disclosure is therefore computed only for a legacy
+        # per-RFC-repo active entry (`repo` set), where edit branches on the
+        # meta repo genuinely predate the per-RFC repo and would otherwise
+        # not appear. After the RFC-0001 fold-back (§13.6) nothing matches.
         pre_grad: list[dict[str, Any]] = []
-        if rfc["state"] == "active":
+        if rfc["state"] == "active" and rfc["repo"]:
             pre_grad_rows = db.conn().execute(
                 """
                 SELECT t.branch_name,
@@ -279,12 +282,33 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/main/promote-to-branch")
     async def promote_to_branch(slug: str, body: PromoteToBranchBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        # v0.16.0 (item #12): cutting a contribute branch is the
+        # PR-shaped write surface gate. A platform-granted user who is
+        # not invited as a per-RFC contributor cannot start work that
+        # only exists to land in a PR.
+        if not auth.can_contribute_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "This RFC's owner has not invited you to contribute PRs",
+            )
+        rfc = _require_active_rfc(slug, viewer)
         owner, repo = _repo_for(rfc)
         new_branch = (body.branch_name or "").strip()
         if not new_branch:
-            new_branch = _auto_branch_name(viewer.gitea_login)
-        _validate_branch_name(new_branch)
+            # Meta-only topology (§1): an active RFC's branches live on the
+            # shared meta repo, so the auto name must embed the slug for the
+            # cache to attribute it (`edit-<slug>-<hex>`, recovered by
+            # `_slug_from_branch_name`). A legacy per-RFC-repo entry can use
+            # the slug-free `<login>-draft-<hex>` since every branch there
+            # belongs to the one RFC. The auto name is trusted (it carries a
+            # reserved `edit-` prefix by design); only a user-supplied name
+            # is validated, mirroring `start_edit_branch`.
+            new_branch = (
+                _auto_edit_branch_name(slug) if _is_meta_resident(rfc)
+                else _auto_branch_name(viewer.gitea_login)
+            )
+        else:
+            _validate_branch_name(new_branch)
         try:
             await bot.cut_branch_from_main(
                 viewer.as_actor(),
@@ -317,8 +341,10 @@ def make_router(
         _ensure_branch_vis(slug, new_branch, creator_user_id=viewer.user_id)
 
         # Make the cache aware immediately so the breadcrumb reflects
-        # the new branch without waiting for the webhook hop.
-        await cache.refresh_rfc_repo(config, gitea, slug)
+        # the new branch without waiting for the webhook hop. Meta-resident
+        # entries (§1) refresh meta branches; a legacy per-RFC repo refreshes
+        # its own — `_refresh_cache_for` dispatches on residency.
+        await _refresh_cache_for(rfc)
 
         return {"branch_name": new_branch, "slug": slug}
 
@@ -331,7 +357,15 @@ def make_router(
     @router.post("/api/rfcs/{slug}/start-edit-branch")
     async def start_edit_branch(slug: str, body: StartEditBranchBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_super_draft(slug)
+        # v0.16.0 (item #12): same per-RFC contribute gate as
+        # promote-to-branch — kicking off a super-draft edit branch is
+        # also PR-shaped work.
+        if not auth.can_contribute_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "This RFC's owner has not invited you to contribute PRs",
+            )
+        rfc = _require_super_draft(slug, viewer)
         owner, repo = _repo_for(rfc)
         new_branch = (body.branch_name or "").strip()
         if not new_branch:
@@ -376,7 +410,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/metadata")
     async def edit_metadata(slug: str, body: MetadataEditBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_super_draft(slug)
+        rfc = _require_super_draft(slug, viewer)
         # Permission: super-draft owners/arbiters per §6.3, plus app-wide
         # admins/owners per §6.1. Until claim, that collapses to admin/owner.
         if not _can_edit_metadata(rfc, viewer):
@@ -449,7 +483,7 @@ def make_router(
         request: Request,
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         _require_can_contribute(slug, branch, viewer)
         row = _require_pending_change(slug, branch, change_id)
         if row["kind"] != "ai":
@@ -536,7 +570,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/changes/{change_id}/decline")
     async def decline_change(slug: str, branch: str, change_id: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         _require_can_contribute(slug, branch, viewer)
         row = _require_pending_change(slug, branch, change_id)
         if row["kind"] != "ai":
@@ -554,7 +588,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/changes/{change_id}/reask")
     async def reask_change(slug: str, branch: str, change_id: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         _require_can_contribute(slug, branch, viewer)
         row = _require_change(slug, branch, change_id)
         if row["kind"] != "ai":
@@ -621,7 +655,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/manual-flush")
     async def manual_flush(slug: str, branch: str, body: ManualFlushBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         _require_can_contribute(slug, branch, viewer)
         owner, repo = _repo_for(rfc, branch)
         path = _file_path_for(rfc, branch)
@@ -698,7 +732,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/visibility")
     async def set_branch_visibility(slug: str, branch: str, body: VisibilityBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         creator = _branch_creator(slug, branch)
         _require_branch_owner(rfc, viewer, creator)
         current = _branch_vis(slug, branch)
@@ -708,7 +742,7 @@ def make_router(
             """
             INSERT INTO branch_visibility (rfc_slug, branch_name, read_public, contribute_mode)
             VALUES (?, ?, ?, ?)
-            ON CONFLICT(rfc_slug, branch_name) DO UPDATE SET
+            ON CONFLICT(collection_id, rfc_slug, branch_name) DO UPDATE SET
                 read_public = excluded.read_public,
                 contribute_mode = excluded.contribute_mode
             """,
@@ -719,7 +753,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/grants")
     async def add_branch_grant(slug: str, branch: str, body: GrantBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         creator = _branch_creator(slug, branch)
         _require_branch_owner(rfc, viewer, creator)
         grantee = db.conn().execute(
@@ -740,7 +774,7 @@ def make_router(
     @router.delete("/api/rfcs/{slug}/branches/{branch:path}/grants/{grantee_login}")
     async def revoke_branch_grant(slug: str, branch: str, grantee_login: str, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         creator = _branch_creator(slug, branch)
         _require_branch_owner(rfc, viewer, creator)
         grantee = db.conn().execute(
@@ -760,7 +794,7 @@ def make_router(
     @router.get("/api/rfcs/{slug}/branches/{branch:path}/threads")
     async def list_branch_threads(slug: str, branch: str, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
         rows = db.conn().execute(
@@ -778,7 +812,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/threads")
     async def create_branch_thread(slug: str, branch: str, body: ThreadCreateBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         if body.thread_kind == "flag" and not body.label:
             raise HTTPException(422, "Flag threads require a label")
         cur = db.conn().execute(
@@ -808,7 +842,7 @@ def make_router(
     @router.get("/api/rfcs/{slug}/branches/{branch:path}/threads/{thread_id}/messages")
     async def get_thread_messages(slug: str, branch: str, thread_id: int, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
         thread = _require_thread(slug, branch, thread_id)
@@ -833,7 +867,7 @@ def make_router(
         slug: str, branch: str, thread_id: int, body: ThreadMessageBody, request: Request
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         _require_thread(slug, branch, thread_id)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
@@ -854,7 +888,7 @@ def make_router(
         to this (slug, branch) on or before the new cursor is marked read.
         """
         viewer = auth.require_user(request)
-        _require_rfc_with_repo(slug)
+        _require_rfc_with_repo(slug, viewer)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
         last_seen = int(body.get("last_seen_message_id") or 0) or None
@@ -862,7 +896,7 @@ def make_router(
             """
             INSERT INTO branch_chat_seen (user_id, rfc_slug, branch_name, last_seen_message_id, seen_at)
             VALUES (?, ?, ?, ?, datetime('now'))
-            ON CONFLICT(user_id, rfc_slug, branch_name) DO UPDATE SET
+            ON CONFLICT(collection_id, user_id, rfc_slug, branch_name) DO UPDATE SET
                 last_seen_message_id = excluded.last_seen_message_id,
                 seen_at = excluded.seen_at
             """,
@@ -877,7 +911,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/threads/{thread_id}/resolve")
     async def resolve_thread(slug: str, branch: str, thread_id: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         thread = _require_thread(slug, branch, thread_id)
         creator = _branch_creator(slug, branch)
         if not _can_resolve_thread(rfc, thread, creator, viewer):
@@ -900,7 +934,7 @@ def make_router(
         slug: str, branch: str, thread_id: int, body: ChatTurnBody, request: Request
     ):
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         thread = _require_thread(slug, branch, thread_id)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
@@ -986,7 +1020,7 @@ def make_router(
     @router.get("/api/rfcs/{slug}/branches/{branch:path}")
     async def get_branch_view(slug: str, branch: str, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        rfc = _require_rfc_with_repo(slug)
+        rfc = _require_rfc_with_repo(slug, viewer)
         if not _can_read_branch(slug, branch, viewer):
             raise HTTPException(403, "Branch is private")
 
@@ -1057,31 +1091,34 @@ def make_router(
     # Permission + state helpers (closures, share `config` etc.)
     # ------------------------------------------------------------------
 
-    def _require_rfc(slug: str):
-        row = db.conn().execute("SELECT * FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
+    def _require_rfc(slug: str, viewer):
+        row = db.conn().execute("SELECT *, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
         if row is None:
             raise HTTPException(404, "RFC not found")
+        # §22.5 visibility gate (subtractive, §22.7): a gated project's entries
+        # 404 to non-members — indistinguishable from an unknown slug.
+        auth.require_project_readable(viewer, row["project_id"])
         return row
 
-    def _require_rfc_with_repo(slug: str):
-        """Used by every branch-scoped endpoint. For active RFCs, a repo is
-        required. For super-drafts, the meta repo is the implicit target —
-        no per-RFC repo check needed."""
-        row = _require_rfc(slug)
+    def _require_rfc_with_repo(slug: str, viewer):
+        """Used by every branch-scoped endpoint. Under the meta-only
+        topology (§1) the meta repo is the implicit target for every
+        entry — super-draft and active alike — so there is no per-RFC
+        repo check. The name is retained for call-site stability; a
+        withdrawn entry is still rejected."""
+        row = _require_rfc(slug, viewer)
         if row["state"] == "withdrawn":
             raise HTTPException(409, "RFC is withdrawn")
-        if row["state"] == "active" and not row["repo"]:
-            raise HTTPException(409, "RFC has no repo")
         return row
 
-    def _require_active_rfc(slug: str):
-        row = _require_rfc_with_repo(slug)
+    def _require_active_rfc(slug: str, viewer):
+        row = _require_rfc_with_repo(slug, viewer)
         if row["state"] != "active":
             raise HTTPException(409, f"RFC is {row['state']}, not active")
         return row
 
-    def _require_super_draft(slug: str):
-        row = _require_rfc(slug)
+    def _require_super_draft(slug: str, viewer):
+        row = _require_rfc(slug, viewer)
         if row["state"] != "super-draft":
             raise HTTPException(409, f"RFC is {row['state']}, not super-draft")
         return row
@@ -1089,28 +1126,34 @@ def make_router(
     def _is_super_draft(rfc) -> bool:
         return rfc["state"] == "super-draft"
 
+    def _is_meta_resident(rfc) -> bool:
+        """Meta-only topology (§1): an entry lives in the meta repo's
+        `rfcs/<slug>.md` (super-draft or active-in-place) unless it carries
+        a legacy per-RFC `repo:` — which nothing does after the RFC-0001
+        fold-back (§13.6)."""
+        return not rfc["repo"]
+
     def _is_meta_branch_name(name: str) -> bool:
         """A branch name shaped like one of the bot's meta-repo prefixes.
-        §9.8's pre-graduation history affordance points the new RFC view
-        at branches matching `edit-<slug>-...` even after the entry is
-        active; treating those names as meta-repo targets lets the read
-        path dispatch correctly without a separate endpoint."""
+        Retained for the legacy per-RFC-repo read path; under meta-only
+        every entry is already a meta target via `_is_meta_resident`."""
         return name != "main" and name.startswith((
             "edit-", "edit/", "metadata-", "metadata/", "claim/", "propose/",
             "graduate-",
         ))
 
     def _is_meta_target(rfc, branch: str) -> bool:
-        """Either a super-draft branch (active edit branch or the
-        canonical body) or an active RFC's pre-graduation meta-repo
-        branch surfaced through the §9.8 history affordance."""
-        if _is_super_draft(rfc):
+        """A meta-resident entry (super-draft or active-in-place, §1)
+        targets the meta repo for every branch. The branch-name fallback
+        covers the retired per-RFC-repo case for any legacy entry that
+        still carries a `repo:`."""
+        if _is_meta_resident(rfc):
             return True
         return _is_meta_branch_name(branch)
 
     def _repo_for(rfc, branch: str = "main") -> tuple[str, str]:
         if _is_meta_target(rfc, branch):
-            return config.gitea_org, config.meta_repo
+            return config.gitea_org, (projects_mod.default_content_repo(config) or "")
         owner, repo = rfc["repo"].split("/", 1)
         return owner, repo
 
@@ -1144,7 +1187,7 @@ def make_router(
         return entry_mod.serialize(entry)
 
     async def _refresh_cache_for(rfc) -> None:
-        if _is_super_draft(rfc):
+        if _is_meta_resident(rfc):
             await cache.refresh_meta_repo(config, gitea)
             await cache.refresh_meta_branches(config, gitea)
         else:
@@ -1221,6 +1264,12 @@ def make_router(
         return row["on_behalf_of"] if row else None
 
     def _can_read_branch(slug: str, branch: str, viewer) -> bool:
+        # §22.5 visibility gate first (subtractive, §B.2): in a hidden/gated
+        # collection nothing — not even main or a read_public branch — is
+        # readable by a non-scope-role viewer.
+        cid = auth.collection_of_rfc(slug)
+        if not auth.can_read_collection(viewer, cid):
+            return False
         if branch == "main":
             return True
         vis = _branch_vis(slug, branch)
@@ -1228,7 +1277,7 @@ def make_router(
             return True
         if viewer is None:
             return False
-        if viewer.role in ("owner", "admin"):
+        if auth.is_collection_superuser(viewer, cid):
             return True
         creator = _branch_creator(slug, branch)
         if creator and viewer.gitea_login == creator:
@@ -1253,14 +1302,20 @@ def make_router(
             return False
         if branch == "main":
             return False
-        # §9.8: pre-graduation history branches are read-only on the
-        # post-graduation surface. The contributor can re-cut against the
-        # new repo's main if they still want the work, but the meta-repo
-        # branches that lived on the super-draft are not editable from
-        # the active-RFC view.
-        if rfc["state"] == "active" and _is_meta_branch_name(branch):
+        # §9.8 (LEGACY per-repo only): pre-graduation history branches are
+        # read-only on the post-graduation surface of a per-RFC-repo active
+        # entry. Under the meta-only topology (§1, §13.4) an active RFC's
+        # `edit-<slug>-…` branches are its *current* editable branches, not
+        # a frozen pre-graduation set, so this guard applies only when a
+        # legacy `repo:` is set (nothing, after the RFC-0001 fold-back).
+        if rfc["state"] == "active" and rfc["repo"] and _is_meta_branch_name(branch):
             return False
-        if viewer.role in ("owner", "admin"):
+        cid = auth.collection_of_rfc(slug)
+        # §22.5 visibility gate (subtractive): no contribute in an unreadable
+        # collection.
+        if not auth.can_read_collection(viewer, cid):
+            return False
+        if auth.is_collection_superuser(viewer, cid):
             return True
         owners = json.loads(rfc["owners_json"] or "[]")
         arbiters = json.loads(rfc["arbiters_json"] or "[]")
@@ -1271,7 +1326,10 @@ def make_router(
             return True
         vis = _branch_vis(slug, branch)
         if vis["contribute_mode"] == "any-contributor":
-            return True
+            # "any contributor" means anyone with collection-level write standing
+            # (§B.2) — the grandfathered baseline on the public default
+            # collection, or an explicit scope grant reaching the collection.
+            return auth.can_contribute_in_collection(viewer, cid)
         if vis["contribute_mode"] == "specific":
             row = db.conn().execute(
                 """
@@ -1285,14 +1343,16 @@ def make_router(
 
     def _require_can_contribute(slug: str, branch: str, viewer) -> None:
         rfc = db.conn().execute(
-            "SELECT state, owners_json, arbiters_json FROM cached_rfcs WHERE slug = ?",
+            "SELECT state, repo, owners_json, arbiters_json FROM cached_rfcs WHERE slug = ?",
             (slug,),
         ).fetchone()
         if not _can_contribute(rfc, slug, branch, viewer):
             raise HTTPException(403, "You do not have contribute access to this branch")
 
     def _require_branch_owner(rfc, viewer, creator: str | None) -> None:
-        if viewer.role in ("owner", "admin"):
+        # §22.6: a project_admin is the per-RFC owner/arbiter authority lifted
+        # to project scope, so it (and a deployment owner/admin) clears here.
+        if auth.is_collection_superuser(viewer, rfc["collection_id"]):
             return
         owners = json.loads(rfc["owners_json"] or "[]")
         arbiters = json.loads(rfc["arbiters_json"] or "[]")
@@ -1303,11 +1363,12 @@ def make_router(
         raise HTTPException(403, "Only the branch creator, an RFC owner/arbiter, or an admin/owner may change branch settings")
 
     def _can_edit_metadata(rfc, viewer) -> bool:
-        """§9.5: super-draft owners/arbiters per §6.3 plus app admins/owners.
-        Until §13.1's claim runs, the super-draft has no owners, so the set
-        collapses to app admins/owners only — sensible because admin oversight
-        is the only path to canonicalizing edits on an unclaimed entry."""
-        if viewer.role in ("owner", "admin"):
+        """§9.5: super-draft owners/arbiters per §6.3 plus project_admin /
+        app admins/owners (§22.6). Until §13.1's claim runs, the super-draft
+        has no owners, so the set collapses to the superuser tier only —
+        sensible because admin oversight is the only path to canonicalizing
+        edits on an unclaimed entry."""
+        if auth.is_collection_superuser(viewer, rfc["collection_id"]):
             return True
         owners = json.loads(rfc["owners_json"] or "[]")
         arbiters = json.loads(rfc["arbiters_json"] or "[]")
@@ -1320,7 +1381,7 @@ def make_router(
             "can_read": _can_read_branch(slug, branch, viewer),
             "can_contribute": _can_contribute(rfc, slug, branch, viewer) if viewer else False,
             "can_change_branch_settings": viewer is not None and (
-                viewer.role in ("owner", "admin")
+                auth.is_collection_superuser(viewer, rfc["collection_id"])
                 or (creator is not None and viewer.gitea_login == creator)
                 or viewer.gitea_login in (owners + arbiters)
             ),
@@ -1366,7 +1427,7 @@ def make_router(
     def _can_resolve_thread(rfc, thread, creator: str | None, viewer) -> bool:
         if viewer is None:
             return False
-        if viewer.role in ("owner", "admin"):
+        if auth.is_collection_superuser(viewer, rfc["collection_id"]):
             return True
         owners = json.loads(rfc["owners_json"] or "[]")
         arbiters = json.loads(rfc["arbiters_json"] or "[]")

backend/app/api_collections.py

@@ -0,0 +1,136 @@
+"""§22 S2 — collection directory + create-collection.
+
+GET  /api/projects/:id/collections        — list the project's visible collections.
+GET  /api/projects/:id/collections/:cid    — one collection's settings.
+POST /api/projects/:id/collections         — create a collection. Authorized by a
+                                             deployment owner/admin (S2; scoped
+                                             {owner, contributor} roles at the
+                                             collection axis land in S3). The bot
+                                             commits a `.collection.yaml` to the
+                                             content repo, then the registry mirror
+                                             upserts the collections row — §22.2
+                                             keeps the registry the source of truth.
+"""
+from __future__ import annotations
+
+import re
+from typing import Any
+
+import yaml
+from fastapi import APIRouter, HTTPException, Request
+from pydantic import BaseModel
+
+from . import (
+    auth,
+    collections as collections_mod,
+    projects as projects_mod,
+    registry as registry_mod,
+)
+from .bot import Bot
+from .config import Config
+from .gitea import Gitea, GiteaError
+
+_SLUG_RE = re.compile(r"^[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$")
+
+
+class CreateCollectionBody(BaseModel):
+    collection_id: str
+    type: str
+    name: str | None = None
+    visibility: str | None = None
+    initial_state: str | None = None
+
+
+def make_router(config: Config, gitea: Gitea, bot: Bot) -> APIRouter:
+    router = APIRouter()
+
+    @router.get("/api/projects/{project_id}/collections")
+    async def list_cols(project_id: str, request: Request) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        # §22.5 read gate: a gated project 404s a non-member.
+        auth.require_project_readable(viewer, project_id)
+        # §22.5 (S3): the directory is viewer-aware — a hidden/gated collection
+        # is listed only for a scope-role holder who can read it; `unlisted` is
+        # omitted from enumeration for everyone (link-only).
+        items = [
+            c
+            for c in collections_mod.list_collections(project_id, include_unlisted=True)
+            if c["visibility"] != "unlisted" and auth.can_read_collection(viewer, c["id"])
+        ]
+        return {"items": items}
+
+    @router.get("/api/projects/{project_id}/collections/{collection_id}")
+    async def get_col(project_id: str, collection_id: str, request: Request) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        auth.require_project_readable(viewer, project_id)
+        col = collections_mod.get_collection(collection_id)
+        if col is None or col["project_id"] != project_id:
+            raise HTTPException(404, "Not found")
+        # §22.5 (S3): a hidden/gated collection 404s a non-scope-role viewer.
+        auth.require_collection_readable(viewer, collection_id)
+        return col
+
+    @router.post("/api/projects/{project_id}/collections")
+    async def create_col(
+        project_id: str, body: CreateCollectionBody, request: Request
+    ) -> dict[str, Any]:
+        # §B.1 (S3) authority: a deployment owner/admin or a project/global-scope
+        # grant holder (Owner or RFC Contributor) may create a collection. The
+        # read gate runs first so a gated project 404s a non-member.
+        user = auth.require_contributor(request)
+        auth.require_project_readable(user, project_id)
+        if not auth.can_create_collection(user, project_id):
+            raise HTTPException(403, "You may not create collections in this project")
+        cid = body.collection_id.strip().lower()
+        if not _SLUG_RE.match(cid) or cid == "default":
+            raise HTTPException(422, "collection id must be a slug and not 'default'")
+        if body.type not in registry_mod.VALID_TYPES:
+            raise HTTPException(422, f"invalid type {body.type!r}")
+        if body.visibility is not None:
+            if body.visibility not in registry_mod.VALID_VISIBILITY:
+                raise HTTPException(422, f"invalid visibility {body.visibility!r}")
+            # §22.5 (S3) strictness: a collection may be set only as strict or
+            # stricter than its project — never more public.
+            pvis = auth.project_visibility(project_id)
+            if auth.visibility_rank(body.visibility) < auth.visibility_rank(pvis):
+                raise HTTPException(
+                    422,
+                    f"collection visibility {body.visibility!r} is looser than "
+                    f"the project's {pvis!r}; a collection may only narrow it",
+                )
+        if body.initial_state is not None and body.initial_state not in registry_mod.VALID_INITIAL_STATE:
+            raise HTTPException(422, f"invalid initial_state {body.initial_state!r}")
+        if collections_mod.get_collection(cid) is not None:
+            raise HTTPException(409, f"collection `{cid}` already exists")
+        content_repo = projects_mod.content_repo(project_id)
+        if not content_repo:
+            raise HTTPException(409, "project has no content repo")
+
+        manifest: dict[str, Any] = {"type": body.type}
+        if body.name:
+            manifest["name"] = body.name
+        if body.visibility:
+            manifest["visibility"] = body.visibility
+        if body.initial_state:
+            manifest["initial_state"] = body.initial_state
+        manifest_yaml = yaml.safe_dump(manifest, sort_keys=False)
+
+        try:
+            await bot.create_collection(
+                user.as_actor(),
+                org=config.gitea_org,
+                content_repo=content_repo,
+                collection_id=cid,
+                manifest_yaml=manifest_yaml,
+            )
+        except GiteaError as e:
+            raise HTTPException(502, f"Gitea: {e.detail}")
+
+        # §22.2: re-read the registry so the new manifest becomes a row.
+        await registry_mod.refresh_registry(config, gitea)
+        col = collections_mod.get_collection(cid)
+        if col is None:
+            raise HTTPException(500, "collection committed but not mirrored")
+        return col
+
+    return router

backend/app/api_contributions.py

@@ -0,0 +1,316 @@
+"""v0.29.0 / roadmap #28 Part 3 — offer-to-contribute-to-a-pending-RFC.
+
+When the #28 scanner (see ``rfc_links.py``) matches a term in submitted
+PR/comment text to a **pending** RFC — a super-draft
+(``cached_rfcs.state='super-draft'``: accepted as an idea, owned, with a
+contribution surface, but not yet graduated to an active RFC) — the
+reader is offered an "ask to contribute" popover. This module is the
+backend for that flow:
+
+  * ``GET  /api/rfcs/{slug}/contribution-target``      — what the
+    contribute form needs (RFC title, owner display, the viewer's
+    eligibility + whether they already have a pending ask).
+  * ``POST /api/rfcs/{slug}/contribution-requests``    — submit the ask
+    (who-I-am / why / optional use-case); lands a row + one §15
+    notification per owner.
+  * ``POST /api/rfcs/{slug}/contribution-requests/{id}/accept``  — owner:
+    accept, which fires #12's owner-invite flow with the requester as the
+    invitee (opening the RFC's discussion/contribution surface), then
+    echoes a notification back to the requester.
+  * ``POST /api/rfcs/{slug}/contribution-requests/{id}/decline`` — owner:
+    decline; the request closes and the requester is notified.
+
+"Pending" is scoped to a super-draft because that is the state with an
+owner to route to, a contribution surface to open, and a row in
+``cached_rfcs`` for the ``rfc_invitations`` FK the accept path reuses.
+Pre-merge idea PRs are deliberately out of scope (no contribution
+surface yet) — a documented future extension, mirroring the
+conservative scoping in ``rfc_links.py``.
+"""
+from __future__ import annotations
+
+import sqlite3
+from typing import Any
+
+from fastapi import APIRouter, HTTPException, Request
+from pydantic import BaseModel, Field
+
+from . import api_invitations, auth, db, notify
+
+# Field caps — generous for free text, bounded so a request row (and the
+# notification payload that carries it) can't be used to store unbounded
+# blobs. Mirrors the order-of-magnitude of the propose/tag-suggest caps.
+_WHO_MAX = 2000
+_WHY_MAX = 4000
+_USE_CASE_MAX = 4000
+_TERM_MAX = 200
+
+
+class ContributionRequestBody(BaseModel):
+    # The term in the PR/comment text that surfaced the offer (the
+    # super-draft's title/slug). Carried for the owner's context line.
+    matched_term: str = Field(min_length=1, max_length=_TERM_MAX)
+    who_i_am: str = Field(min_length=1, max_length=_WHO_MAX)
+    why: str = Field(min_length=1, max_length=_WHY_MAX)
+    use_case: str | None = Field(default=None, max_length=_USE_CASE_MAX)
+
+
+def _require_super_draft(slug: str, viewer):
+    """The contribute surface only operates on a *pending* RFC. 404 on
+    unknown; 409 on a state that isn't a super-draft (active RFCs use the
+    Part-1 link, not a contribute offer; withdrawn is closed). The §22.5
+    visibility gate is subtractive: a gated project's entries 404 to
+    non-members (§22.7)."""
+    row = db.conn().execute(
+        "SELECT slug, title, state, owners_json, proposed_by, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?",
+        (slug,),
+    ).fetchone()
+    if row is None:
+        raise HTTPException(404, "RFC not found")
+    auth.require_project_readable(viewer, row["project_id"])
+    if row["state"] != "super-draft":
+        raise HTTPException(409, "RFC is not a pending super-draft")
+    return row
+
+
+def _require_request(slug: str, request_id: int):
+    row = db.conn().execute(
+        """
+        SELECT id, rfc_slug, requester_user_id, matched_term, who_i_am, why,
+               use_case, status
+          FROM contribution_requests WHERE id = ? AND rfc_slug = ?
+        """,
+        (request_id, slug),
+    ).fetchone()
+    if row is None:
+        raise HTTPException(404, "Contribution request not found")
+    return row
+
+
+def _viewer_relationship(viewer, slug: str) -> str | None:
+    """Why this viewer can't *request* to contribute — or None if they can.
+    Owners/admins already have the RFC; existing collaborators are already
+    in. Both get a clear 409 rather than a useless self-request."""
+    if auth.is_rfc_owner(viewer, slug) or auth.is_collection_superuser(viewer, auth.collection_of_rfc(slug)):
+        return "You already own or administer this RFC."
+    if auth.is_rfc_collaborator(viewer, slug):
+        return "You're already a collaborator on this RFC."
+    return None
+
+
+def make_router() -> APIRouter:
+    router = APIRouter()
+
+    # ---------------------------------------------------------------
+    # GET — what the contribute form needs to render + gate itself.
+    # ---------------------------------------------------------------
+
+    @router.get("/api/rfcs/{slug}/contribution-target")
+    async def contribution_target(slug: str, request: Request) -> dict[str, Any]:
+        row = db.conn().execute(
+            "SELECT slug, title, state, owners_json, proposed_by, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?",
+            (slug,),
+        ).fetchone()
+        if row is None:
+            raise HTTPException(404, "RFC not found")
+        viewer = auth.current_user(request)
+        # §22.5 visibility gate (subtractive): gated → 404 to non-members.
+        auth.require_project_readable(viewer, row["project_id"])
+
+        from . import rfc_links  # local import: avoid a module import cycle
+
+        owner = rfc_links._owner_display(db.conn(), row["owners_json"], row["proposed_by"])
+
+        eligible = True
+        reason: str | None = None
+        already_requested = False
+        if row["state"] != "super-draft":
+            eligible, reason = False, "This RFC is no longer pending."
+        elif viewer is None:
+            eligible, reason = False, "Sign in to ask to contribute."
+        elif viewer.permission_state != "granted":
+            eligible, reason = False, "Your beta access request is in review."
+        else:
+            reason = _viewer_relationship(viewer, slug)
+            if reason is not None:
+                eligible = False
+            else:
+                already_requested = bool(
+                    db.conn().execute(
+                        """
+                        SELECT 1 FROM contribution_requests
+                         WHERE rfc_slug = ? AND requester_user_id = ? AND status = 'pending'
+                         LIMIT 1
+                        """,
+                        (slug, viewer.user_id),
+                    ).fetchone()
+                )
+
+        return {
+            "slug": row["slug"],
+            "title": row["title"],
+            "owner": owner,
+            "eligible": eligible and not already_requested,
+            "reason": reason,
+            "already_requested": already_requested,
+        }
+
+    # ---------------------------------------------------------------
+    # POST — submit a contribute request.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/{slug}/contribution-requests")
+    async def create_contribution_request(
+        slug: str, body: ContributionRequestBody, request: Request
+    ) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        _require_super_draft(slug, viewer)
+
+        reason = _viewer_relationship(viewer, slug)
+        if reason is not None:
+            raise HTTPException(409, reason)
+
+        who_i_am = body.who_i_am.strip()
+        why = body.why.strip()
+        use_case = (body.use_case or "").strip() or None
+        matched_term = body.matched_term.strip()
+        if not who_i_am or not why:
+            raise HTTPException(422, "Both 'who I am' and 'why' are required.")
+
+        try:
+            cur = db.conn().execute(
+                """
+                INSERT INTO contribution_requests
+                    (rfc_slug, requester_user_id, matched_term, who_i_am, why, use_case)
+                VALUES (?, ?, ?, ?, ?, ?)
+                """,
+                (slug, viewer.user_id, matched_term, who_i_am, why, use_case),
+            )
+        except sqlite3.IntegrityError:
+            # The partial unique index — one open request per (RFC, user).
+            raise HTTPException(409, "You already have a pending request to contribute to this RFC.")
+        request_id = cur.lastrowid
+
+        # One actionable notification per owner; stamp the first onto the
+        # row as the inbox-action handle (any owner can act on the request).
+        notif_ids = notify.fan_out_contribution_request(
+            rfc_slug=slug,
+            requester_user_id=viewer.user_id,
+            request_id=request_id,
+            matched_term=matched_term,
+            who_i_am=who_i_am,
+            why=why,
+            use_case=use_case,
+        )
+        if notif_ids:
+            db.conn().execute(
+                "UPDATE contribution_requests SET notification_id = ? WHERE id = ?",
+                (notif_ids[0], request_id),
+            )
+
+        return {"id": request_id, "rfc_slug": slug, "status": "pending"}
+
+    # ---------------------------------------------------------------
+    # POST — owner accepts → fire #12's invite flow.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/{slug}/contribution-requests/{request_id}/accept")
+    async def accept_contribution_request(
+        slug: str, request_id: int, request: Request
+    ) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        rfc = _require_super_draft(slug, viewer)
+        if not auth.can_invite_to_rfc(viewer, slug):
+            raise HTTPException(403, "Only the RFC's owner can act on contribution requests")
+
+        req = _require_request(slug, request_id)
+        if req["status"] != "pending":
+            raise HTTPException(409, f"This request was already {req['status']}.")
+
+        requester = db.conn().execute(
+            "SELECT id, email FROM users WHERE id = ?", (req["requester_user_id"],)
+        ).fetchone()
+        if requester is None or not (requester["email"] or "").strip():
+            raise HTTPException(422, "The requester has no email address on file to invite.")
+
+        # Fire #12's owner-invite flow with the requester as the invitee.
+        # If a pending contributor invitation already exists (the owner
+        # invited them out-of-band first), reuse it rather than failing.
+        try:
+            invitation = api_invitations.issue_invitation(
+                slug=slug,
+                inviter_user_id=viewer.user_id,
+                inviter_display=viewer.display_name or viewer.gitea_login or "An RFC owner",
+                invitee_email=requester["email"],
+                role_in_rfc="contributor",
+                rfc_title=rfc["title"],
+            )
+            invitation_id = invitation["id"]
+        except HTTPException as exc:
+            if exc.status_code != 409:
+                raise
+            existing = db.conn().execute(
+                """
+                SELECT id FROM rfc_invitations
+                 WHERE rfc_slug = ? AND invitee_email = ? COLLATE NOCASE
+                   AND role_in_rfc = 'contributor' AND status = 'pending'
+                 ORDER BY id DESC LIMIT 1
+                """,
+                (slug, requester["email"].strip()),
+            ).fetchone()
+            invitation_id = existing["id"] if existing else None
+
+        db.conn().execute(
+            """
+            UPDATE contribution_requests
+               SET status = 'accepted', decided_at = datetime('now'),
+                   decided_by_user_id = ?, invitation_id = ?
+             WHERE id = ?
+            """,
+            (viewer.user_id, invitation_id, request_id),
+        )
+        notify.notify_contribution_decided(
+            rfc_slug=slug,
+            requester_user_id=req["requester_user_id"],
+            decider_user_id=viewer.user_id,
+            request_id=request_id,
+            accepted=True,
+        )
+        return {"ok": True, "status": "accepted", "invitation_id": invitation_id}
+
+    # ---------------------------------------------------------------
+    # POST — owner declines.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/{slug}/contribution-requests/{request_id}/decline")
+    async def decline_contribution_request(
+        slug: str, request_id: int, request: Request
+    ) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        _require_super_draft(slug, viewer)
+        if not auth.can_invite_to_rfc(viewer, slug):
+            raise HTTPException(403, "Only the RFC's owner can act on contribution requests")
+
+        req = _require_request(slug, request_id)
+        if req["status"] != "pending":
+            raise HTTPException(409, f"This request was already {req['status']}.")
+
+        db.conn().execute(
+            """
+            UPDATE contribution_requests
+               SET status = 'declined', decided_at = datetime('now'),
+                   decided_by_user_id = ?
+             WHERE id = ?
+            """,
+            (viewer.user_id, request_id),
+        )
+        notify.notify_contribution_decided(
+            rfc_slug=slug,
+            requester_user_id=req["requester_user_id"],
+            decider_user_id=viewer.user_id,
+            request_id=request_id,
+            accepted=False,
+        )
+        return {"ok": True, "status": "declined"}
+
+    return router

backend/app/api_deployment.py

@@ -0,0 +1,123 @@
+"""§22.9 runtime deployment/project config (replaces VITE_APP_NAME) + §22.10
+old-URL 308 redirects.
+
+GET /api/deployment — the deployment name/tagline + the projects the caller can
+see (§22.5: gated filtered by membership, unlisted omitted from enumeration),
+plus the corpus-served `default_project_id` the M3-frontend guard keys on.
+GET /api/projects/:id — one project's runtime config + optional theme overlay,
+gated behind the §22.5 read gate (404 for a non-member of a gated project).
+GET /rfc/{slug}, /proposals/{n} — §22.10 server-side 308s onto the new
+`/p/<default>/…` routes (the SPA no longer owns these paths; nginx proxies them
+to the backend instead of serving index.html).
+"""
+from __future__ import annotations
+
+import json
+from typing import Any
+
+from fastapi import APIRouter, HTTPException, Request
+from fastapi.responses import RedirectResponse
+
+from . import auth, collections as collections_mod, db, projects as projects_mod
+from .config import Config
+
+
+def make_router(config: Config) -> APIRouter:
+    router = APIRouter()
+
+    @router.get("/api/deployment")
+    async def get_deployment(request: Request) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        dep = db.conn().execute(
+            "SELECT name, tagline FROM deployment WHERE id = 1"
+        ).fetchone()
+        # §22.5: enumerate only public + (member-)gated; unlisted is never listed.
+        visible = set(auth.visible_project_ids(viewer))
+        # §22 three-tier: `type` is a per-corpus field on the (default) collection
+        # now; surface the default collection's type for each project.
+        rows = db.conn().execute(
+            "SELECT id, name, visibility FROM projects "
+            "WHERE visibility != 'unlisted' ORDER BY name"
+        ).fetchall()
+        projects = [
+            {
+                "id": r["id"],
+                "name": r["name"],
+                "type": collections_mod.collection_type(
+                    collections_mod.default_collection_id(r["id"])
+                ),
+                "visibility": r["visibility"],
+            }
+            for r in rows
+            if r["id"] in visible
+        ]
+        return {
+            "name": (dep["name"] if dep else "") or "",
+            "tagline": (dep["tagline"] if dep else "") or "",
+            # §22.10 / M3-frontend guard contract: which project the backend
+            # serves the corpus for (the default, until Plan B serves per
+            # project). The frontend renders corpus routes only for this id and
+            # shows a "content not yet served" placeholder for any other.
+            "default_project_id": projects_mod.resolved_default_id(config),
+            "projects": projects,
+        }
+
+    @router.get("/api/projects/{project_id}")
+    async def get_project(project_id: str, request: Request) -> dict[str, Any]:
+        viewer = auth.current_user(request)
+        # §22.5 read gate: a gated project 404s to a non-member (shape matches
+        # an unknown id). unlisted is readable by direct id.
+        auth.require_project_readable(viewer, project_id)
+        row = db.conn().execute(
+            "SELECT id, name, visibility, config_json FROM projects WHERE id = ?",
+            (project_id,),
+        ).fetchone()
+        if row is None:
+            raise HTTPException(status_code=404, detail="Not found")
+        try:
+            cfg = json.loads(row["config_json"] or "{}")
+        except (ValueError, TypeError):
+            cfg = {}
+        dep = db.conn().execute("SELECT tagline FROM deployment WHERE id = 1").fetchone()
+        # §22 three-tier: type + initial_state moved down to the (default)
+        # collection in migration 029.
+        cid = collections_mod.default_collection_id(row["id"])
+        return {
+            "id": row["id"],
+            "name": row["name"],
+            "tagline": (dep["tagline"] if dep else "") or "",
+            "type": collections_mod.collection_type(cid),
+            "visibility": row["visibility"],
+            "initial_state": collections_mod.collection_initial_state(cid),
+            "theme": cfg.get("theme") or {},
+        }
+
+    # §22.10 / §5 — server-side 308s off the old corpus-root URLs onto the
+    # `/p/<default>/…` routes. 308 (not 301/302) preserves method + body and
+    # is permanent, so external "RFC-0001" links and bookmarks land correctly.
+    # nginx routes /rfc/ and /proposals/ to the backend so these are reached
+    # before the SPA's index.html fallback.
+    # §22 three-tier (S1): the canonical entry route now carries the collection
+    # segment /p/<project>/c/<collection>/…. The legacy roots redirect through
+    # the default project's default collection.
+    @router.get("/rfc/{slug}")
+    async def redirect_old_rfc(slug: str) -> RedirectResponse:
+        default_id = projects_mod.resolved_default_id(config)
+        cid = collections_mod.default_collection_id(default_id)
+        return RedirectResponse(url=f"/p/{default_id}/c/{cid}/e/{slug}", status_code=308)
+
+    @router.get("/rfc/{slug}/pr/{pr_number}")
+    async def redirect_old_rfc_pr(slug: str, pr_number: int) -> RedirectResponse:
+        default_id = projects_mod.resolved_default_id(config)
+        cid = collections_mod.default_collection_id(default_id)
+        return RedirectResponse(
+            url=f"/p/{default_id}/c/{cid}/e/{slug}/pr/{pr_number}", status_code=308
+        )
+
+    @router.get("/proposals/{pr_number}")
+    async def redirect_old_proposal(pr_number: int) -> RedirectResponse:
+        default_id = projects_mod.resolved_default_id(config)
+        cid = collections_mod.default_collection_id(default_id)
+        return RedirectResponse(url=f"/p/{default_id}/c/{cid}/proposals/{pr_number}", status_code=308)
+
+    return router

backend/app/api_discussion.py

@@ -40,7 +40,7 @@ from typing import Any
 from fastapi import APIRouter, HTTPException, Request
 from pydantic import BaseModel, Field
 
-from . import auth, chat as chat_layer, db
+from . import auth, chat as chat_layer, db, rfc_links
 
 log = logging.getLogger(__name__)
 
@@ -84,7 +84,7 @@ def make_router() -> APIRouter:
     @router.get("/api/rfcs/{slug}/discussion/threads")
     async def list_discussion_threads(slug: str, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        _require_rfc_readable(slug)
+        _require_rfc_readable(slug, viewer)
         # Ensure the default whole-doc discussion thread exists. We mint
         # it on first read regardless of viewer (anonymous viewers can
         # trigger the creation — the row's `created_by` is null in that
@@ -115,7 +115,18 @@ def make_router() -> APIRouter:
         slug: str, body: DiscussionThreadCreateBody, request: Request
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_rfc_readable(slug)
+        _require_rfc_readable(slug, viewer)
+        # v0.16.0 (roadmap item #12): the per-RFC discussion is now a
+        # gated surface. The platform-level `require_contributor` above
+        # ensures the user is signed in + admin-granted; this layer
+        # narrows further to "is this user named for this RFC?" The
+        # 403 here is structurally the v0.6.0 anon-write refusal
+        # extended to non-invited platform users.
+        if not auth.can_discuss_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "This RFC's owner has not invited you to its discussion",
+            )
         cur = db.conn().execute(
             """
             INSERT INTO threads
@@ -144,8 +155,8 @@ def make_router() -> APIRouter:
     async def get_discussion_thread_messages(
         slug: str, thread_id: int, request: Request
     ) -> dict[str, Any]:
-        _viewer = auth.current_user(request)
-        _require_rfc_readable(slug)
+        viewer = auth.current_user(request)
+        _require_rfc_readable(slug, viewer)
         thread = _require_discussion_thread(slug, thread_id)
         rows = db.conn().execute(
             """
@@ -160,9 +171,17 @@ def make_router() -> APIRouter:
             """,
             (thread_id,),
         ).fetchall()
+        # Roadmap #28 Part 1: enrich each discussion comment with RFC
+        # auto-link segments scanned against the live accepted-RFC corpus
+        # (read-time; see rfc_links.py). exclude_slug suppresses self-links
+        # to this RFC inside its own discussion.
+        link_index = rfc_links.build_index(db.conn(), exclude_slug=slug)
+        messages = [_serialize_message(r) for r in rows]
+        for m in messages:
+            m["text_segments"] = link_index.segment(m["text"])
         return {
             "thread": _serialize_thread(thread),
-            "messages": [_serialize_message(r) for r in rows],
+            "messages": messages,
         }
 
     # -------------------------------------------------------------------
@@ -174,7 +193,13 @@ def make_router() -> APIRouter:
         slug: str, thread_id: int, body: DiscussionMessageBody, request: Request
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_rfc_readable(slug)
+        _require_rfc_readable(slug, viewer)
+        # v0.16.0 (item #12): same per-RFC gate as create_discussion_thread.
+        if not auth.can_discuss_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "This RFC's owner has not invited you to its discussion",
+            )
         _require_discussion_thread(slug, thread_id)
         message_id = chat_layer.append_user_message(
             thread_id=thread_id,
@@ -193,7 +218,7 @@ def make_router() -> APIRouter:
         slug: str, thread_id: int, request: Request
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_rfc_readable(slug)
+        rfc = _require_rfc_readable(slug, viewer)
         thread = _require_discussion_thread(slug, thread_id)
         if not _can_resolve(rfc, thread, viewer):
             raise HTTPException(
@@ -220,17 +245,24 @@ def make_router() -> APIRouter:
 # ---------------------------------------------------------------------------
 
 
-def _require_rfc_readable(slug: str):
-    """Per the v0.3.0 anonymous-read contract: any cached RFC is readable
-    by anyone. Withdrawn entries refuse reads of every shape — same rule
-    `_require_rfc_with_repo` in `api_branches.py` follows."""
+def _require_rfc_readable(slug: str, viewer):
+    """Per the v0.3.0 anonymous-read contract: any cached RFC in a *readable*
+    project is readable by anyone. The §22.5 visibility gate is subtractive on
+    top (§22.7): a gated project's entries 404 to non-members. Withdrawn
+    entries refuse reads of every shape — same rule `_require_rfc_with_repo`
+    in `api_branches.py` follows."""
     row = db.conn().execute(
-        "SELECT * FROM cached_rfcs WHERE slug = ?", (slug,)
+        "SELECT *, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?", (slug,)
     ).fetchone()
     if row is None:
         raise HTTPException(404, "RFC not found")
+    auth.require_project_readable(viewer, row["project_id"])
     if row["state"] == "withdrawn":
         raise HTTPException(409, "RFC is withdrawn")
+    # §13.7: a retired entry is soft-deleted — refuse reads of every shape
+    # (a 404, not a 409: the entry is not surfaced anywhere a browser looks).
+    if row["state"] == "retired":
+        raise HTTPException(404, "RFC not found")
     return row
 
 
@@ -280,7 +312,7 @@ def _ensure_discussion_thread(slug: str, viewer) -> int:
 def _can_resolve(rfc, thread, viewer) -> bool:
     if viewer is None:
         return False
-    if viewer.role in ("owner", "admin"):
+    if auth.is_collection_superuser(viewer, rfc["collection_id"]):
         return True
     owners = json.loads(rfc["owners_json"] or "[]")
     arbiters = json.loads(rfc["arbiters_json"] or "[]")

backend/app/api_invitations.py

@@ -0,0 +1,596 @@
+"""v0.16.0 / §6 / §10 — owner-only invite for per-RFC PR or PR-less
+discussion (roadmap item #12).
+
+The RFC's owner can invite a specific email to one of two per-RFC roles:
+
+  * `contributor` — may open PRs against this RFC AND post in its
+    discussion (PR-permission strictly includes discussion-permission).
+  * `discussant` — may post in this RFC's PR-less discussion only.
+
+Non-invited users keep the v0.6.0 anonymous-read contract: they can
+read but cannot write/discuss the RFC. Reads are not narrowed by
+this item.
+
+Endpoints:
+
+  * `POST   /api/rfcs/{slug}/invitations`              — owner: create + email
+  * `GET    /api/rfcs/{slug}/invitations`              — owner: list pending/accepted
+  * `POST   /api/rfcs/{slug}/invitations/{id}/revoke`  — owner: revoke
+  * `GET    /api/invitations/accept`                   — token lookup (signed-in user)
+  * `POST   /api/invitations/accept`                   — token redeem (signed-in user)
+
+The accept endpoints are deliberately platform-scoped (not nested under
+the RFC slug) because the user clicking the email link only has the
+token and may not even know the slug yet. The GET shape lets the
+frontend show a confirmation page ("RFC <X> invited you to be a
+<role> — accept?") before the POST commits the membership.
+
+Permission gates (composed with `require_contributor`):
+
+  * Issue / list / revoke: `auth.can_invite_to_rfc` — RFC owner or
+    platform admin/owner.
+  * Accept: any platform-granted signed-in user; the gate is the
+    token, not the role. The token also constrains which email the
+    accept lands under — the accepting user's email must match the
+    invitation's invitee_email (case-insensitive). This prevents an
+    invited-but-not-the-account-holder situation from minting a
+    collaborator row under the wrong identity.
+
+Email shape: a single plain-text body sent via the existing SMTP path
+(reuses `EmailConfig.from_env()` like `email_otc.py` does). No
+unsubscribe footer — the email is transactional and per-invite, not a
+recurring notification. No tracking pixel.
+
+Admin-page hook: when an accept lands and the user's
+`permission_state` is still `pending`, that signals to the admin's
+`/admin/users` queue that the user is here because they accepted a
+per-RFC invitation — informing (not deciding) the admin's
+platform-grant call. v0.16.0 surfaces this via additive columns on
+the existing `GET /api/admin/users` listing (see `api_admin.py`'s
+diff in the same release) — no new endpoint, no restructure.
+"""
+from __future__ import annotations
+
+import logging
+import secrets
+import smtplib
+from email.message import EmailMessage
+from email.utils import formataddr
+from typing import Any
+
+from fastapi import APIRouter, HTTPException, Request
+from pydantic import BaseModel, Field
+
+from . import auth, db
+from .email import EmailConfig, _SENT
+
+log = logging.getLogger(__name__)
+
+
+# ---------------------------------------------------------------------------
+# Pydantic bodies
+# ---------------------------------------------------------------------------
+
+
+class CreateInvitationBody(BaseModel):
+    """The owner picks an email and a role-in-RFC. No custom-message
+    field — that belongs to item #16's platform-level invite surface,
+    not here.
+
+    We validate the email with a deliberately narrow pattern rather
+    than `pydantic.EmailStr` to avoid pulling in `email-validator` as
+    a dependency (and v0.7.0's OTC body does the same — see
+    `OTCRequestBody`'s shape). The validation here is intentionally
+    permissive: a local-part, an `@`, and a domain part with no
+    whitespace. Operator-side typo catching is the job of the email
+    transport; the framework only guards against obviously malformed
+    input."""
+    invitee_email: str = Field(min_length=3, max_length=320,
+                               pattern=r"^[^\s@]+@[^\s@]+$")
+    role_in_rfc: str = Field(pattern="^(contributor|discussant)$")
+
+
+class AcceptInvitationBody(BaseModel):
+    token: str = Field(min_length=1, max_length=200)
+
+
+# ---------------------------------------------------------------------------
+# Constants
+# ---------------------------------------------------------------------------
+
+
+# 30-day TTL matches the device-trust window the framework already
+# ships (v0.11.0). A pending invitation past this is rejected at the
+# accept endpoint regardless of the row's `status` column.
+INVITATION_TTL_DAYS = 30
+
+
+# ---------------------------------------------------------------------------
+# Router
+# ---------------------------------------------------------------------------
+
+
+def make_router() -> APIRouter:
+    router = APIRouter()
+
+    # ---------------------------------------------------------------
+    # POST /api/rfcs/<slug>/invitations
+    # The owner creates an invitation. The endpoint mints the token,
+    # writes the row, and dispatches the email synchronously. A failure
+    # to send the email does NOT roll back the row — the owner can
+    # share the link directly out-of-band if SMTP is briefly down (the
+    # `GET /api/rfcs/<slug>/invitations` response carries the token
+    # for that fallback).
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/{slug}/invitations")
+    async def create_invitation(slug: str, body: CreateInvitationBody, request: Request) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        rfc = _require_rfc(slug, viewer)
+        if not auth.can_invite_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "Only the RFC's owner can invite collaborators",
+            )
+
+        return issue_invitation(
+            slug=slug,
+            inviter_user_id=viewer.user_id,
+            inviter_display=viewer.display_name or viewer.gitea_login or "An RFC owner",
+            invitee_email=body.invitee_email,
+            role_in_rfc=body.role_in_rfc,
+            rfc_title=rfc["title"],
+        )
+
+    # ---------------------------------------------------------------
+    # GET /api/rfcs/<slug>/invitations
+    # The owner's listing of every invitation on the RFC, regardless
+    # of status. Carries the token (for the resend / re-share path).
+    # ---------------------------------------------------------------
+
+    @router.get("/api/rfcs/{slug}/invitations")
+    async def list_invitations(slug: str, request: Request) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        _require_rfc(slug, viewer)
+        if not auth.can_invite_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "Only the RFC's owner can view invitations",
+            )
+
+        rows = db.conn().execute(
+            """
+            SELECT i.id, i.invitee_email, i.role_in_rfc, i.status, i.token,
+                   i.expires_at, i.created_at, i.accepted_at,
+                   i.inviter_user_id, i.accepted_by_user_id,
+                   u_inviter.display_name AS inviter_display,
+                   u_inviter.gitea_login AS inviter_login,
+                   u_accept.display_name AS accepted_by_display,
+                   u_accept.gitea_login AS accepted_by_login
+              FROM rfc_invitations i
+         LEFT JOIN users u_inviter ON u_inviter.id = i.inviter_user_id
+         LEFT JOIN users u_accept ON u_accept.id = i.accepted_by_user_id
+             WHERE i.rfc_slug = ?
+             ORDER BY i.id DESC
+            """,
+            (slug,),
+        ).fetchall()
+
+        return {
+            "items": [
+                {
+                    "id": r["id"],
+                    "invitee_email": r["invitee_email"],
+                    "role_in_rfc": r["role_in_rfc"],
+                    "status": _effective_status(r),
+                    "token": r["token"],
+                    "expires_at": r["expires_at"],
+                    "created_at": r["created_at"],
+                    "accepted_at": r["accepted_at"],
+                    "inviter_display": r["inviter_display"],
+                    "inviter_login": r["inviter_login"],
+                    "accepted_by_display": r["accepted_by_display"],
+                    "accepted_by_login": r["accepted_by_login"],
+                }
+                for r in rows
+            ],
+        }
+
+    # ---------------------------------------------------------------
+    # POST /api/rfcs/<slug>/invitations/<id>/revoke
+    # Revokes a pending invitation. Already-accepted invitations
+    # cannot be "revoked" from this surface — the corresponding
+    # collaborator-removal surface is a §19.2 candidate; v0.16.0
+    # only lifts the *pending* link.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/rfcs/{slug}/invitations/{invitation_id}/revoke")
+    async def revoke_invitation(slug: str, invitation_id: int, request: Request) -> dict[str, Any]:
+        viewer = auth.require_contributor(request)
+        _require_rfc(slug, viewer)
+        if not auth.can_invite_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "Only the RFC's owner can revoke invitations",
+            )
+
+        row = db.conn().execute(
+            "SELECT id, status FROM rfc_invitations WHERE id = ? AND rfc_slug = ?",
+            (invitation_id, slug),
+        ).fetchone()
+        if row is None:
+            raise HTTPException(404, "Invitation not found")
+        if row["status"] != "pending":
+            raise HTTPException(
+                409,
+                f"Invitation is {row['status']}; only pending invitations can be revoked",
+            )
+
+        db.conn().execute(
+            "UPDATE rfc_invitations SET status = 'revoked' WHERE id = ?",
+            (invitation_id,),
+        )
+        return {"ok": True, "id": invitation_id, "status": "revoked"}
+
+    # ---------------------------------------------------------------
+    # GET /api/invitations/accept?token=...
+    # Lookup-only — returns what the invitation grants so the
+    # frontend can render a confirmation page before the POST. The
+    # token is required; no token, no peek.
+    # ---------------------------------------------------------------
+
+    @router.get("/api/invitations/accept")
+    async def preview_invitation(token: str, request: Request) -> dict[str, Any]:
+        viewer = auth.require_user(request)
+        row = _lookup_invitation_by_token(token)
+        if row is None:
+            raise HTTPException(404, "Invitation not found")
+        effective = _effective_status(row)
+        rfc = db.conn().execute(
+            "SELECT slug, title FROM cached_rfcs WHERE slug = ?", (row["rfc_slug"],),
+        ).fetchone()
+        return {
+            "rfc_slug": row["rfc_slug"],
+            "rfc_title": rfc["title"] if rfc else row["rfc_slug"],
+            "role_in_rfc": row["role_in_rfc"],
+            "status": effective,
+            "invitee_email": row["invitee_email"],
+            "email_matches_you": (viewer.email or "").strip().lower()
+                                == row["invitee_email"].strip().lower(),
+            "expires_at": row["expires_at"],
+        }
+
+    # ---------------------------------------------------------------
+    # POST /api/invitations/accept
+    # The accept gesture: token → collaborator row.
+    #
+    # Requires:
+    #   * an authenticated user (no token-only acceptance — we want
+    #     the per-user audit trail),
+    #   * a valid (pending, non-expired, non-revoked) invitation,
+    #   * the accepting user's email matches invitee_email
+    #     (case-insensitive).
+    #
+    # On success the row's status flips to 'accepted' and a
+    # rfc_collaborators row is inserted (or upgraded if the user
+    # already had a lower role). Idempotent: re-accepting the same
+    # already-accepted invitation reads as a 200 no-op with
+    # `changed=false`.
+    # ---------------------------------------------------------------
+
+    @router.post("/api/invitations/accept")
+    async def accept_invitation(body: AcceptInvitationBody, request: Request) -> dict[str, Any]:
+        viewer = auth.require_user(request)
+        row = _lookup_invitation_by_token(body.token)
+        if row is None:
+            raise HTTPException(404, "Invitation not found")
+
+        effective = _effective_status(row)
+        if effective == "revoked":
+            raise HTTPException(409, "Invitation was revoked")
+        if effective == "expired":
+            raise HTTPException(409, "Invitation has expired")
+
+        # Email match — case-insensitive. Empty viewer email cannot
+        # accept (an OAuth-only user with no captured email shape).
+        viewer_email = (viewer.email or "").strip().lower()
+        invitee_email = row["invitee_email"].strip().lower()
+        if not viewer_email or viewer_email != invitee_email:
+            raise HTTPException(
+                403,
+                "This invitation was sent to a different email; sign in with that address",
+            )
+
+        if effective == "accepted":
+            # Idempotent re-accept — surface the existing collaborator
+            # row without writing anything new.
+            collab = db.conn().execute(
+                "SELECT role_in_rfc FROM rfc_collaborators WHERE rfc_slug = ? AND user_id = ?",
+                (row["rfc_slug"], viewer.user_id),
+            ).fetchone()
+            return {
+                "ok": True,
+                "changed": False,
+                "rfc_slug": row["rfc_slug"],
+                "role_in_rfc": collab["role_in_rfc"] if collab else row["role_in_rfc"],
+            }
+
+        # First-time accept. Flip the invitation; upsert the
+        # collaborator. We do the upsert with ON CONFLICT so a
+        # user who already held a lower role gets upgraded, never
+        # downgraded (the MAX-style precedence is contributor >
+        # discussant; lower roles never overwrite higher).
+        with db.tx() as c:
+            c.execute(
+                """
+                UPDATE rfc_invitations
+                   SET status = 'accepted',
+                       accepted_at = datetime('now'),
+                       accepted_by_user_id = ?
+                 WHERE id = ?
+                """,
+                (viewer.user_id, row["id"]),
+            )
+            existing = c.execute(
+                "SELECT role_in_rfc FROM rfc_collaborators WHERE rfc_slug = ? AND user_id = ?",
+                (row["rfc_slug"], viewer.user_id),
+            ).fetchone()
+            target_role = _max_role(
+                existing["role_in_rfc"] if existing else None,
+                row["role_in_rfc"],
+            )
+            if existing is None:
+                c.execute(
+                    """
+                    INSERT INTO rfc_collaborators
+                        (rfc_slug, user_id, role_in_rfc, invitation_id)
+                    VALUES (?, ?, ?, ?)
+                    """,
+                    (row["rfc_slug"], viewer.user_id, target_role, row["id"]),
+                )
+            elif existing["role_in_rfc"] != target_role:
+                c.execute(
+                    """
+                    UPDATE rfc_collaborators
+                       SET role_in_rfc = ?, invitation_id = ?
+                     WHERE rfc_slug = ? AND user_id = ?
+                    """,
+                    (target_role, row["id"], row["rfc_slug"], viewer.user_id),
+                )
+
+        return {
+            "ok": True,
+            "changed": True,
+            "rfc_slug": row["rfc_slug"],
+            "role_in_rfc": target_role,
+        }
+
+    return router
+
+
+# ---------------------------------------------------------------------------
+# Helpers
+# ---------------------------------------------------------------------------
+
+
+def _require_rfc(slug: str, viewer):
+    """The invitation surface only operates on a known, non-withdrawn
+    RFC. We refuse 404 on unknown and 409 on withdrawn — mirrors the
+    discussion endpoints' `_require_rfc_readable` shape. The §22.5
+    visibility gate is subtractive: a gated project's entries 404 to
+    non-members (§22.7)."""
+    row = db.conn().execute(
+        "SELECT slug, title, state, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?", (slug,),
+    ).fetchone()
+    if row is None:
+        raise HTTPException(404, "RFC not found")
+    auth.require_project_readable(viewer, row["project_id"])
+    if row["state"] == "withdrawn":
+        raise HTTPException(409, "RFC is withdrawn")
+    return row
+
+
+def _lookup_invitation_by_token(token: str):
+    return db.conn().execute(
+        """
+        SELECT id, rfc_slug, inviter_user_id, invitee_email, role_in_rfc,
+               status, token, expires_at, created_at, accepted_at,
+               accepted_by_user_id
+          FROM rfc_invitations
+         WHERE token = ?
+        """,
+        (token,),
+    ).fetchone()
+
+
+def _effective_status(row) -> str:
+    """The row's column status is the authoritative truth except for
+    `expired` — that is derived from `expires_at` at read time so an
+    unattended cron isn't required to flip rows. A revoked-then-
+    expired row reads as `revoked` (the explicit gesture wins)."""
+    column_status = row["status"]
+    if column_status != "pending":
+        return column_status
+    # Compare via SQL so the comparison is in sqlite-time, matching the
+    # `datetime('now')` insert. A simpler same-process comparison would
+    # work too, but routing through the DB keeps the timezone handling
+    # consistent with the inserts.
+    is_past = db.conn().execute(
+        "SELECT datetime(?) <= datetime('now') AS past",
+        (row["expires_at"],),
+    ).fetchone()["past"]
+    return "expired" if is_past else "pending"
+
+
+def issue_invitation(
+    *,
+    slug: str,
+    inviter_user_id: int,
+    inviter_display: str,
+    invitee_email: str,
+    role_in_rfc: str,
+    rfc_title: str,
+) -> dict:
+    """Mint + persist + email one ``rfc_invitations`` row.
+
+    The single chokepoint for issuing an invitation: the owner's manual
+    `POST /api/rfcs/{slug}/invitations` endpoint and roadmap #28 Part 3's
+    accept path both route through here, so the dup-guard, token mint,
+    insert, and transactional email stay identical.
+
+    Refuses (409) re-inviting an email that already has a pending
+    invitation on this RFC at the same role. A different-role re-invite is
+    allowed (the discussant → contributor upgrade) — the new row
+    supersedes the old in the listing's natural ordering, and acceptance
+    of either picks up the corresponding role.
+
+    Returns the new row's dict (including the raw token, for the owner's
+    out-of-band share / the caller's record-keeping). A send failure logs
+    and returns; the row stays so the owner can recover via the listing.
+    """
+    invitee_email = invitee_email.strip()
+    existing = db.conn().execute(
+        """
+        SELECT id FROM rfc_invitations
+         WHERE rfc_slug = ? AND invitee_email = ? COLLATE NOCASE
+           AND role_in_rfc = ? AND status = 'pending'
+         LIMIT 1
+        """,
+        (slug, invitee_email, role_in_rfc),
+    ).fetchone()
+    if existing:
+        raise HTTPException(
+            409,
+            f"{invitee_email} already has a pending {role_in_rfc} invitation for this RFC",
+        )
+
+    token = _mint_token()
+    cur = db.conn().execute(
+        """
+        INSERT INTO rfc_invitations
+            (rfc_slug, inviter_user_id, invitee_email, role_in_rfc,
+             token, expires_at)
+        VALUES (?, ?, ?, ?, ?, datetime('now', ?))
+        """,
+        (slug, inviter_user_id, invitee_email, role_in_rfc, token, f"+{INVITATION_TTL_DAYS} days"),
+    )
+    invitation_id = cur.lastrowid
+
+    _send_invitation_email(
+        to_address=invitee_email,
+        inviter_display=inviter_display,
+        rfc_title=rfc_title,
+        role_in_rfc=role_in_rfc,
+        token=token,
+    )
+
+    return {
+        "id": invitation_id,
+        "rfc_slug": slug,
+        "invitee_email": invitee_email,
+        "role_in_rfc": role_in_rfc,
+        "status": "pending",
+        "token": token,
+    }
+
+
+def _mint_token() -> str:
+    """A 256-bit URL-safe token. The token shape is opaque to the
+    consumer; the email link encodes it as a query param."""
+    return secrets.token_urlsafe(32)
+
+
+def _max_role(existing: str | None, new: str) -> str:
+    """contributor strictly dominates discussant. A re-accept that
+    would lower the role is a no-op (the existing role survives)."""
+    precedence = {"discussant": 0, "contributor": 1}
+    if existing is None:
+        return new
+    if precedence.get(new, 0) > precedence.get(existing, 0):
+        return new
+    return existing
+
+
+# ---------------------------------------------------------------------------
+# Email dispatch — transactional, no preferences honored
+# ---------------------------------------------------------------------------
+
+
+def _send_invitation_email(
+    *,
+    to_address: str,
+    inviter_display: str,
+    rfc_title: str,
+    role_in_rfc: str,
+    token: str,
+) -> bool:
+    """Compose and send the invitation email.
+
+    Like `email_otc.send_otc_email`, this writes its own envelope and
+    reuses `EmailConfig.from_env()` for the SMTP plumbing. The
+    `_SENT` buffer is appended either way so integration tests can
+    assert on the outbound shape without a real SMTP server.
+
+    Returns True on the happy path / dev fallback; False on SMTP
+    failure. The caller does not roll back the invitation row on
+    failure — the owner has the token in the create response and on
+    the listing surface for an out-of-band share.
+    """
+    cfg = EmailConfig.from_env()
+    subject = f"{inviter_display} invited you to {rfc_title} on {cfg.from_name}"
+    role_label = (
+        "open PRs against the RFC and join its discussion"
+        if role_in_rfc == "contributor"
+        else "join the RFC's discussion"
+    )
+    link = f"{cfg.app_url}/invitations/accept?token={token}"
+    body = (
+        f"{inviter_display} invited you to {rfc_title} on {cfg.from_name} as {role_in_rfc}.\n\n"
+        f"This invitation lets you {role_label}.\n\n"
+        f"Click to accept (you'll be asked to sign in first if you aren't already):\n\n"
+        f"    {link}\n\n"
+        f"The invitation expires in {INVITATION_TTL_DAYS} days. If you weren't expecting\n"
+        f"this, you can safely ignore the email.\n\n"
+        f"---\n"
+        f"{cfg.from_name} · {cfg.app_url}\n"
+    )
+    envelope = {
+        "to": to_address,
+        "from": formataddr((cfg.from_name, cfg.from_address)),
+        "subject": subject,
+        "body": body,
+        "kind": "rfc_invitation",
+    }
+    _SENT.append(envelope)
+
+    if not cfg.enabled:
+        log.info("invitation email disabled (EMAIL_ENABLED=0): to=%s", to_address)
+        return True
+    if not cfg.smtp_host:
+        # Dev fallback — surface the link at INFO so the operator can
+        # complete an accept flow without an SMTP relay.
+        log.info(
+            "invitation email (stdout fallback): to=%s rfc=%s role=%s link=%s",
+            to_address, rfc_title, role_in_rfc, link,
+        )
+        return True
+
+    try:
+        msg = EmailMessage()
+        msg["From"] = envelope["from"]
+        msg["To"] = to_address
+        msg["Subject"] = subject
+        msg.set_content(body)
+        smtp = smtplib.SMTP(cfg.smtp_host, cfg.smtp_port, timeout=30)
+        try:
+            if cfg.smtp_starttls:
+                smtp.starttls()
+            if cfg.smtp_user:
+                smtp.login(cfg.smtp_user, cfg.smtp_password)
+            smtp.send_message(msg)
+        finally:
+            smtp.quit()
+        return True
+    except Exception:
+        log.exception("invitation email send failed: to=%s", to_address)
+        return False

backend/app/api_notifications.py

@@ -73,6 +73,13 @@ class MarkReadBody(BaseModel):
 class BounceBody(BaseModel):
     email: str = Field(min_length=3, max_length=320)
     kind: str = Field(default="hard")  # 'hard' or 'complaint'
+    # v0.18.0 Slice 5: when the bounce provider includes the
+    # original Message-ID, the framework correlates it back to
+    # the matching `outbound_emails` row and stamps
+    # `status='bounced'`. Optional — providers that don't surface
+    # the Message-ID still flip the global opt-out via the email
+    # match, but lose the per-message attribution.
+    message_id: str | None = Field(default=None, max_length=1000)
 
 
 class CookieConsentBody(BaseModel):
@@ -206,14 +213,16 @@ def make_router(config: Config) -> APIRouter:
     @router.post("/api/rfcs/{slug}/watch")
     async def set_watch(slug: str, body: WatchBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_user(request)
-        rfc = db.conn().execute("SELECT slug FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
+        rfc = db.conn().execute("SELECT (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
         if rfc is None:
             raise HTTPException(404, "RFC not found")
+        # §22.5 visibility gate (subtractive): gated → 404 to non-members.
+        auth.require_project_readable(viewer, rfc["project_id"])
         db.conn().execute(
             """
             INSERT INTO watches (user_id, rfc_slug, state, set_by, set_at, last_participation_at)
             VALUES (?, ?, ?, 'explicit', datetime('now'), datetime('now'))
-            ON CONFLICT(user_id, rfc_slug) DO UPDATE SET
+            ON CONFLICT(collection_id, user_id, rfc_slug) DO UPDATE SET
                 state = excluded.state,
                 set_by = 'explicit',
                 set_at = excluded.set_at
@@ -443,6 +452,40 @@ def make_router(config: Config) -> APIRouter:
 
     # ----- Email: one-click unsubscribe + bounce webhook -----
 
+    # v0.18.0: the category → column map. The `all` synthetic
+    # category lands the bundle's one-click on the global opt-out
+    # flag (per `email._send_bundle` in v0.18.0 Slice 2 — a bundle
+    # spans multiple categories, so a per-category flip wouldn't
+    # honor the user's intent).
+    _CATEGORY_COLUMN: dict[str, str] = {
+        "personal-direct": "email_personal_direct",
+        "structural": "email_watched_structural",
+        "admin-actionable": "email_admin_actionable",
+        "all": "email_opt_out_all",
+    }
+
+    def _apply_unsubscribe(user_id: int, category: str) -> bool:
+        """Flip the matching column. Returns True on success, False
+        if the category is unknown. Idempotent — running twice on
+        the same (user, category) is harmless (it sets the column
+        to its current value)."""
+        column = _CATEGORY_COLUMN.get(category)
+        if column is None:
+            return False
+        # `all` sets the flag to 1 (opt out); per-category sets to 0
+        # (turn that category off). The column semantic is "1 means
+        # don't send"; the per-category booleans are "1 means do
+        # send". Different polarities, hence the case split.
+        if category == "all":
+            db.conn().execute(
+                f"UPDATE users SET {column} = 1 WHERE id = ?", (user_id,)
+            )
+        else:
+            db.conn().execute(
+                f"UPDATE users SET {column} = 0 WHERE id = ?", (user_id,)
+            )
+        return True
+
     @router.get("/api/email/unsubscribe")
     async def email_unsubscribe(t: str = Query(..., description="Signed token from the email footer")) -> HTMLResponse:
         try:
@@ -453,20 +496,51 @@ def make_router(config: Config) -> APIRouter:
                 "<p>Open the app to manage your notification preferences directly.</p>",
                 status_code=400,
             )
-        column = {
-            "personal-direct": "email_personal_direct",
-            "structural": "email_watched_structural",
-            "admin-actionable": "email_admin_actionable",
-        }.get(category)
-        if column is None:
+        if not _apply_unsubscribe(user_id, category):
             return HTMLResponse(
                 f"<h1>Unknown category</h1><p>{category}</p>", status_code=400
             )
-        db.conn().execute(f"UPDATE users SET {column} = 0 WHERE id = ?", (user_id,))
-        return HTMLResponse(
-            f"<h1>Unsubscribed</h1><p>You will no longer receive {category} emails. "
-            f"You can re-enable them in your notification preferences.</p>"
-        )
+        if category == "all":
+            body = (
+                "<h1>Unsubscribed</h1><p>You will no longer receive any email "
+                "from this app. You can re-enable individual categories from "
+                "your notification preferences after signing in.</p>"
+            )
+        else:
+            body = (
+                f"<h1>Unsubscribed</h1><p>You will no longer receive {category} emails. "
+                f"You can re-enable them in your notification preferences.</p>"
+            )
+        return HTMLResponse(body)
+
+    @router.post("/api/email/unsubscribe")
+    async def email_unsubscribe_post(
+        request: Request,
+        t: str = Query(..., description="Signed token from the List-Unsubscribe header"),
+    ) -> dict[str, Any]:
+        """v0.18.0: RFC 8058 one-click endpoint.
+
+        Gmail and Yahoo POST `List-Unsubscribe=One-Click` (as a
+        form-encoded body) to the URL in the `List-Unsubscribe`
+        header when the user clicks their MUA's "Unsubscribe"
+        button. The endpoint MUST accept POST (per the
+        `List-Unsubscribe-Post` header we advertise) and MUST be
+        idempotent.
+
+        The body content is checked loosely — RFC 8058 says it
+        SHOULD be exactly `List-Unsubscribe=One-Click`, but some
+        intermediaries strip / re-encode the body, so the
+        framework accepts any POST to the URL once the token
+        verifies. The bar is that the token signature carries the
+        authority; the body is hint-only.
+        """
+        try:
+            user_id, category = email_mod.verify_unsubscribe_token(t)
+        except BadSignature:
+            raise HTTPException(400, "Invalid or expired token")
+        if not _apply_unsubscribe(user_id, category):
+            raise HTTPException(400, f"Unknown category: {category}")
+        return {"ok": True, "category": category}
 
     @router.post("/api/webhooks/email-bounce")
     async def email_bounce(body: BounceBody, request: Request) -> dict[str, Any]:
@@ -485,21 +559,70 @@ def make_router(config: Config) -> APIRouter:
         # stays unauthenticated for dev (the v1 contract).
         import os as _os
         expected = _os.environ.get("WEBHOOK_EMAIL_BOUNCE_SECRET", "").strip()
-        if expected:
+        # v0.25.0 (audit 0026 M5): fail closed. An unset secret used to
+        # leave this endpoint fully unauthenticated — anyone could suppress
+        # any user's mail by POSTing their address (email_opt_out_all flip
+        # below). Now an unset secret DISABLES the endpoint (503) instead
+        # of opening it. A dev that genuinely wants it open opts in
+        # explicitly with RFC_APP_INSECURE_BOUNCE_WEBHOOK=1, mirroring the
+        # RFC_APP_INSECURE_WEBHOOKS dev-bypass on the Gitea hook.
+        if not expected:
+            if _os.environ.get("RFC_APP_INSECURE_BOUNCE_WEBHOOK", "").strip() == "1":
+                log.warning(
+                    "email-bounce webhook running UNAUTHENTICATED "
+                    "(RFC_APP_INSECURE_BOUNCE_WEBHOOK=1) — never set this in production"
+                )
+            else:
+                log.error(
+                    "email-bounce webhook refused: WEBHOOK_EMAIL_BOUNCE_SECRET is unset "
+                    "(set the secret to enable, or RFC_APP_INSECURE_BOUNCE_WEBHOOK=1 for dev)"
+                )
+                raise HTTPException(503, "Bounce webhook not configured")
+        else:
             received = request.headers.get("X-Webhook-Secret", "")
             import hmac as _hmac
             if not received or not _hmac.compare_digest(expected, received):
                 raise HTTPException(401, "Invalid webhook signature")
+        # v0.18.0 Slice 5: correlate the bounce back to the
+        # matching outbound_emails row if the provider supplied
+        # the Message-ID. The hard-bounce -> global-opt-out
+        # logic below still fires regardless; this is an
+        # additional audit signal.
+        correlated_row_id: int | None = None
+        if body.message_id:
+            correlated = db.conn().execute(
+                "SELECT id FROM outbound_emails WHERE message_id = ?",
+                (body.message_id,),
+            ).fetchone()
+            if correlated is not None:
+                correlated_row_id = correlated["id"]
+                db.conn().execute(
+                    "UPDATE outbound_emails SET status = 'bounced', "
+                    "error = COALESCE(error, '') || ? WHERE id = ?",
+                    (f"bounce ({body.kind})", correlated_row_id),
+                )
+                log.info(
+                    "email-bounce: correlated message_id=%s -> outbound_emails.id=%s",
+                    body.message_id, correlated_row_id,
+                )
+            else:
+                log.info(
+                    "email-bounce: message_id=%s did not match any "
+                    "outbound_emails row (provider may be replaying an old bounce, "
+                    "or the row was pruned)",
+                    body.message_id,
+                )
+
         row = db.conn().execute(
             "SELECT id FROM users WHERE LOWER(email) = LOWER(?)", (body.email,),
         ).fetchone()
         if row is None:
-            return {"ok": True, "matched": False}
+            return {"ok": True, "matched": False, "correlated_id": correlated_row_id}
         db.conn().execute(
             "UPDATE users SET email_opt_out_all = 1 WHERE id = ?", (row["id"],),
         )
         log.info("email-bounce: opted out user %s (%s)", row["id"], body.kind)
-        return {"ok": True, "matched": True}
+        return {"ok": True, "matched": True, "correlated_id": correlated_row_id}
 
     return router
 

backend/app/api_prs.py

@@ -23,7 +23,7 @@ from typing import Any
 from fastapi import APIRouter, HTTPException, Request
 from pydantic import BaseModel, Field
 
-from . import auth, cache, chat as chat_layer, db, entry as entry_mod, funder, models_resolver
+from . import auth, cache, chat as chat_layer, db, entry as entry_mod, funder, models_resolver, projects as projects_mod, rfc_links
 from .bot import Bot
 from .config import Config
 from .gitea import Gitea, GiteaError
@@ -42,6 +42,11 @@ RFC_FILE_PATH = "RFC.md"
 class OpenPRBody(BaseModel):
     title: str = Field(min_length=1, max_length=240)
     description: str = Field(max_length=8000)
+    # Roadmap #26: optional "What will you be using this change for?" —
+    # the concrete ground-truth use case sibling to the required
+    # "why is this change needed" (the `description`). Optional, generous
+    # cap matching the description bound.
+    proposed_use_case: str | None = Field(default=None, max_length=8000)
 
 
 class PRDescriptionBody(BaseModel):
@@ -80,7 +85,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/pr-draft")
     async def draft_pr_text(slug: str, branch: str, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         owner, repo = _owner_repo(rfc)
         path = _file_path_for(rfc)
         if not _branch_has_commits_ahead(slug, branch):
@@ -112,7 +117,18 @@ def make_router(
     @router.post("/api/rfcs/{slug}/branches/{branch:path}/open-pr")
     async def open_pr(slug: str, branch: str, body: OpenPRBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        # v0.16.0 (item #12): opening a PR is the canonical PR-shaped
+        # write — the gate fires here even though the branch-cutting
+        # entry points also gate, since a user with prior branch access
+        # who's since had their per-RFC role revoked shouldn't be able
+        # to ship the PR. The branch-creation gate is the kickoff
+        # refusal; this one is the post-work refusal.
+        if not auth.can_contribute_to_rfc(viewer, slug):
+            raise HTTPException(
+                403,
+                "This RFC's owner has not invited you to contribute PRs",
+            )
+        rfc = _require_active_rfc(slug, viewer)
         if branch == "main":
             raise HTTPException(409, "PRs open from non-main branches")
         owner, repo = _owner_repo(rfc)
@@ -137,7 +153,7 @@ def make_router(
             """
             INSERT INTO branch_visibility (rfc_slug, branch_name, read_public, contribute_mode)
             VALUES (?, ?, 1, 'just-me')
-            ON CONFLICT(rfc_slug, branch_name) DO UPDATE SET read_public = 1
+            ON CONFLICT(collection_id, rfc_slug, branch_name) DO UPDATE SET read_public = 1
             """,
             (slug, branch),
         )
@@ -162,6 +178,26 @@ def make_router(
             raise HTTPException(502, f"Gitea: {e.detail}")
 
         await _refresh_after_pr_write(rfc)
+
+        # Roadmap #26: persist the optional use case to the canonical,
+        # reconcile-proof side table keyed by the PR number. Blank/omitted
+        # writes no row (absence == "left blank"). The mirror onto
+        # cached_prs keeps the cache column in parity.
+        use_case = (body.proposed_use_case or "").strip()
+        if use_case:
+            db.conn().execute(
+                """
+                INSERT INTO proposed_use_cases (scope, rfc_slug, pr_number, use_case)
+                VALUES ('pr', ?, ?, ?)
+                ON CONFLICT(collection_id, scope, pr_number) DO UPDATE SET use_case = excluded.use_case
+                """,
+                (slug, pr["number"], use_case),
+            )
+            db.conn().execute(
+                "UPDATE cached_prs SET proposed_use_case = ? WHERE rfc_slug = ? AND pr_number = ?",
+                (use_case, slug, pr["number"]),
+            )
+
         return {"pr_number": pr["number"], "slug": slug, "branch": branch}
 
     # -------------------------------------------------------------------
@@ -171,12 +207,18 @@ def make_router(
     @router.get("/api/rfcs/{slug}/prs/{pr_number}")
     async def get_pr(slug: str, pr_number: int, request: Request) -> dict[str, Any]:
         viewer = auth.current_user(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         owner, repo = _owner_repo(rfc)
         path = _file_path_for(rfc)
         head_branch = pr_row["head_branch"]
 
+        # Roadmap #28 Part 1: build the RFC auto-link index once for this
+        # PR view (read-time enrichment against the live accepted-RFC
+        # corpus; see rfc_links.py). exclude_slug suppresses self-links to
+        # this RFC inside its own PR.
+        link_index = rfc_links.build_index(db.conn(), exclude_slug=slug)
+
         # §11.3: PRs are always public; no visibility check.
         main_fetched = await gitea.read_file(owner, repo, path, ref="main")
         main_body = _extract_body(rfc, (main_fetched or ("", ""))[0])
@@ -223,6 +265,13 @@ def make_router(
             for r in msg_rows:
                 messages_by_thread.setdefault(r["thread_id"], []).append(_serialize_message(r))
 
+        # Roadmap #28 Part 1: enrich every comment with RFC auto-link
+        # segments (read-time; see rfc_links.py). The description is
+        # enriched alongside it in the return dict below.
+        for _msgs in messages_by_thread.values():
+            for _m in _msgs:
+                _m["text_segments"] = link_index.segment(_m["text"])
+
         # Per-user seen cursor per §10.3. Anonymous viewers get no
         # cursor — they always see "everything new" but cannot advance
         # the cursor (no row to write to).
@@ -289,6 +338,8 @@ def make_router(
             "pr_number": pr_number,
             "title": pr_row["title"],
             "description": pr_row["description"],
+            "description_segments": link_index.segment(pr_row["description"]),
+            "proposed_use_case": _pr_use_case(pr_number),
             "state": pr_row["state"],
             "opened_by": pr_row["opened_by"],
             "opened_at": pr_row["opened_at"],
@@ -322,7 +373,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/prs/{pr_number}/seen")
     async def advance_seen(slug: str, pr_number: int, body: PRSeenBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_active_rfc(slug)
+        _require_active_rfc(slug, viewer)
         _require_pr(slug, pr_number)
         # Take the max of stored and incoming for both cursors so a
         # stale tab firing a seen-cursor advance after a fresher tab
@@ -347,7 +398,7 @@ def make_router(
             INSERT INTO pr_seen
                 (user_id, rfc_slug, pr_number, last_seen_commit_sha, last_seen_message_id, seen_at)
             VALUES (?, ?, ?, ?, ?, datetime('now'))
-            ON CONFLICT(user_id, rfc_slug, pr_number) DO UPDATE SET
+            ON CONFLICT(collection_id, user_id, rfc_slug, pr_number) DO UPDATE SET
                 last_seen_commit_sha = excluded.last_seen_commit_sha,
                 last_seen_message_id = excluded.last_seen_message_id,
                 seen_at = excluded.seen_at
@@ -369,7 +420,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/prs/{pr_number}/review")
     async def post_review_thread(slug: str, pr_number: int, body: PRReviewBody, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        _require_active_rfc(slug)
+        _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         head_branch = pr_row["head_branch"]
         cur = db.conn().execute(
@@ -396,7 +447,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/prs/{pr_number}/merge")
     async def merge_pr(slug: str, pr_number: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         if not _can_merge(rfc, viewer):
             raise HTTPException(403, "Only arbiters, RFC owners, and app admins/owners may merge")
@@ -428,7 +479,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/prs/{pr_number}/withdraw")
     async def withdraw_pr(slug: str, pr_number: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         if not _can_withdraw(rfc, pr_row, viewer):
             raise HTTPException(403, "Only the contributor or an RFC owner/arbiter (or app admin/owner) may withdraw")
@@ -459,7 +510,7 @@ def make_router(
         slug: str, pr_number: int, body: PRDescriptionBody, request: Request
     ) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         if not _can_edit_pr_text(rfc, pr_row, viewer):
             raise HTTPException(403, "Only the contributor or an RFC owner/arbiter (or admin/owner) may edit")
@@ -484,7 +535,7 @@ def make_router(
     @router.post("/api/rfcs/{slug}/prs/{pr_number}/resolution-branch")
     async def start_resolution_branch(slug: str, pr_number: int, request: Request) -> dict[str, Any]:
         viewer = auth.require_contributor(request)
-        rfc = _require_active_rfc(slug)
+        rfc = _require_active_rfc(slug, viewer)
         pr_row = _require_pr(slug, pr_number)
         if pr_row["state"] != "open":
             raise HTTPException(409, f"PR is {pr_row['state']}, not open")
@@ -552,7 +603,7 @@ def make_router(
             repo=repo,
             slug=slug,
             file_path=_file_path_for(rfc),
-            is_super_draft=_is_super_draft(rfc),
+            is_super_draft=_is_meta_resident(rfc),
             original_branch=original_branch,
             resolution_branch=resolution_branch,
         )
@@ -610,42 +661,49 @@ def make_router(
     # Helpers (closures over config/gitea/etc.)
     # ------------------------------------------------------------------
 
-    def _require_rfc(slug: str):
-        row = db.conn().execute("SELECT * FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
+    def _require_rfc(slug: str, viewer):
+        row = db.conn().execute("SELECT *, (SELECT c.project_id FROM collections c WHERE c.id = cached_rfcs.collection_id) AS project_id FROM cached_rfcs WHERE slug = ?", (slug,)).fetchone()
         if row is None:
             raise HTTPException(404, "RFC not found")
+        # §22.5 visibility gate (subtractive, §22.7) — even §11.3 "PRs always
+        # public" yields to a gated project: non-members get 404.
+        auth.require_project_readable(viewer, row["project_id"])
         return row
 
-    def _require_active_rfc(slug: str):
+    def _require_active_rfc(slug: str, viewer):
         """Used by the §10 PR-flow read and write paths. Per §17's routing-
         collapse rule, a super-draft RFC also routes here — its body-edit
         PRs are meta-repo PRs with pr_kind='meta_body_edit', but the API
-        surface is identical."""
-        row = _require_rfc(slug)
+        surface is identical. Under the meta-only topology (§1) an active
+        RFC is meta-resident too (repo is null) — that is normal, not an
+        error, so there is no per-RFC-repo precondition."""
+        row = _require_rfc(slug, viewer)
         if row["state"] not in ("active", "super-draft"):
             raise HTTPException(409, f"RFC is {row['state']}")
-        if row["state"] == "active" and not row["repo"]:
-            raise HTTPException(409, "RFC has no repo")
         return row
 
-    def _is_super_draft(rfc) -> bool:
-        return rfc["state"] == "super-draft"
+    def _is_meta_resident(rfc) -> bool:
+        """Meta-only topology (§1): an entry lives in the meta repo's
+        `rfcs/<slug>.md` (super-draft or active-in-place) unless it carries
+        a legacy per-RFC `repo:` — which nothing does after the RFC-0001
+        fold-back (§13.6). Drives the body/path/repo dispatch below."""
+        return not rfc["repo"]
 
     def _owner_repo(rfc) -> tuple[str, str]:
-        if _is_super_draft(rfc):
-            return config.gitea_org, config.meta_repo
+        if _is_meta_resident(rfc):
+            return config.gitea_org, (projects_mod.default_content_repo(config) or "")
         owner, repo = rfc["repo"].split("/", 1)
         return owner, repo
 
     def _file_path_for(rfc) -> str:
-        if _is_super_draft(rfc):
+        if _is_meta_resident(rfc):
             return f"rfcs/{rfc['slug']}.md"
         return RFC_FILE_PATH
 
     def _extract_body(rfc, file_contents: str) -> str:
-        """For super-draft entries the file on disk is the full
+        """For meta-resident entries the file on disk is the full
         frontmatter+body envelope; the editable body is entry.body."""
-        if not _is_super_draft(rfc):
+        if not _is_meta_resident(rfc):
             return file_contents
         try:
             entry = entry_mod.parse(file_contents)
@@ -709,7 +767,7 @@ def make_router(
         return row["original_pr_number"] if row else None
 
     async def _refresh_after_pr_write(rfc) -> None:
-        if _is_super_draft(rfc):
+        if _is_meta_resident(rfc):
             await cache.refresh_meta_repo(config, gitea)
             await cache.refresh_meta_branches(config, gitea)
             await cache.refresh_meta_pulls(config, gitea)
@@ -725,10 +783,10 @@ def make_router(
 
 
 def _can_merge(rfc, viewer) -> bool:
-    """§6.1 admin/owner OR §6.3 RFC owners/arbiters."""
+    """§6.1 admin/owner or §22.6 project_admin OR §6.3 RFC owners/arbiters."""
     if viewer is None:
         return False
-    if viewer.role in ("owner", "admin"):
+    if auth.is_collection_superuser(viewer, rfc["collection_id"]):
         return True
     owners = json.loads(rfc["owners_json"] or "[]")
     arbiters = json.loads(rfc["arbiters_json"] or "[]")
@@ -751,6 +809,17 @@ def _can_edit_pr_text(rfc, pr_row, viewer) -> bool:
     return _can_withdraw(rfc, pr_row, viewer)
 
 
+def _pr_use_case(pr_number: int) -> str | None:
+    """Roadmap #26: the optional propose-PR use case from the canonical
+    side table, or None when the change was opened without one ("left
+    blank")."""
+    row = db.conn().execute(
+        "SELECT use_case FROM proposed_use_cases WHERE scope = 'pr' AND pr_number = ?",
+        (pr_number,),
+    ).fetchone()
+    return row["use_case"] if row else None
+
+
 def _pr_capabilities(rfc, pr_row, viewer) -> dict:
     return {
         "can_merge": _can_merge(rfc, viewer) and pr_row["state"] == "open",

backend/app/auth.py

@@ -16,9 +16,11 @@ from typing import Any
 import httpx
 from fastapi import HTTPException, Request
 
+from . import collections as collections_mod
 from . import db
 from .bot import Actor
 from .config import Config
+from .projects import DEFAULT_PROJECT_ID
 
 
 @dataclass
@@ -290,5 +292,575 @@ def require_admin(request: Request) -> SessionUser:
     return user
 
 
+# ===========================================================================
+# §22.6 / §22.7 — project-scoped authorization (the multi-project middle tier).
+#
+# A deployment hosts N projects (§22). Authorization for an action on an RFC is
+# the *most-permissive union* of three tiers — the actor's deployment role
+# (§6.1), their project role (§22.6), and their per-RFC authority (§6.3/§12) —
+# with the §22.5 visibility gate and the §6.2 write-mute *subtractive* on top
+# (§22.7). The per-RFC capability helpers below (`can_discuss_rfc`,
+# `can_contribute_to_rfc`, `can_invite_to_rfc`) compose all three tiers, so the
+# ~20 endpoint call sites inherit multi-project behavior unchanged.
+#
+# Through Slice M2 the only project is the migration-seeded `default` one (the
+# N=1 case, §22.13); a project is resolved from an RFC slug via
+# `cached_rfcs.project_id` (unique per slug while N=1). M3's registry mirror
+# lets a deployment declare a second project; these gates already hold then.
+#
+# OPERATOR DECISIONS (M2):
+#  * implicit-on-public — on a `public` project a granted deployment
+#    `contributor` keeps the pre-multi-project write *baseline* (propose
+#    freely; an owned RFC's discuss/contribute is still gated by the v0.16.0
+#    per-RFC invite). No project_members row is needed and no backfill runs,
+#    so the N=1 case stays whole. Explicit project_members rows and
+#    gated/unlisted visibility are where the new tier actually bites.
+#  * preserve curation — the implicit-public baseline does NOT override per-RFC
+#    owner curation; only an *explicit* project_contributor/project_admin grant
+#    (or a deployment owner/admin) bypasses it. So §22.7's "project_contributor
+#    ⊇ rfc_collaborators(contributor)" holds for explicit grants, while a plain
+#    granted contributor on public behaves exactly as it did before M2.
+# ===========================================================================
+
+_DEPLOYMENT_SUPERUSER_ROLES = ("owner", "admin")
+
+
+def project_visibility(project_id: str) -> str:
+    """The project's §22.5 visibility ('gated' | 'public' | 'unlisted'). A
+    missing row reads as 'gated' — the safe default: an unknown project is
+    invisible rather than open."""
+    row = db.conn().execute(
+        "SELECT visibility FROM projects WHERE id = ?", (project_id,)
+    ).fetchone()
+    if row is None:
+        return "gated"
+    return row["visibility"] or "gated"
+
+
+def _is_default_project(project_id: str) -> bool:
+    """True iff `project_id` owns the migration-seeded `default` collection — the
+    deployment's primary project (§22.13), whatever its configured id. Only there
+    do M2's role rows (which migrated to collection scope `default`) stand in for
+    project-level authority."""
+    return collections_mod.project_of_collection(collections_mod.DEFAULT_COLLECTION_ID) == project_id
+
+
+def project_member_role(user: SessionUser | None, project_id: str) -> str | None:
+    """The user's *project-grain* §22.6 role at this project, or None — the
+    most-permissive of a **global** grant (inherits down to every project) and a
+    **project**-scope grant. Mapped back to the legacy
+    `project_admin`/`project_contributor` strings the project-grain authz speaks.
+
+    Back-compat: on the deployment's *default* project only, M2's rows live at
+    collection scope `default` (§B.3 migration), so a `default` collection-scope
+    grant there is read as project-level too. A collection grant on any other
+    project is NOT project authority — that is the four-layer collection resolver
+    (`effective_scope_role`). Does not fold in the deployment tier
+    (`is_project_superuser` adds it) or the implicit-on-public baseline."""
+    if user is None:
+        return None
+    clauses = ["scope_type = 'global'", "(scope_type = 'project' AND scope_id = ?)"]
+    params: list = [user.user_id, project_id]
+    if _is_default_project(project_id):
+        clauses.append("(scope_type = 'collection' AND scope_id = ?)")
+        params.append(collections_mod.DEFAULT_COLLECTION_ID)
+    row = db.conn().execute(
+        "SELECT role FROM memberships WHERE user_id = ? AND (" + " OR ".join(clauses) + ") "
+        "ORDER BY CASE role WHEN 'owner' THEN 0 ELSE 1 END LIMIT 1",
+        params,
+    ).fetchone()
+    if row is None:
+        return None
+    return "project_admin" if row["role"] == "owner" else "project_contributor"
+
+
+def project_of_rfc(rfc_slug: str) -> str:
+    """The project an RFC belongs to, via its collection
+    (`cached_rfcs.collection_id` -> `collections.project_id`, §22 three-tier).
+    Falls back to the default project when the slug isn't cached — the same N=1
+    default migration 026 backfills."""
+    row = db.conn().execute(
+        "SELECT c.project_id AS project_id "
+        "FROM cached_rfcs r JOIN collections c ON c.id = r.collection_id "
+        "WHERE r.slug = ?",
+        (rfc_slug,),
+    ).fetchone()
+    if row is None:
+        return DEFAULT_PROJECT_ID
+    return row["project_id"] or DEFAULT_PROJECT_ID
+
+
+def collection_of_rfc(rfc_slug: str) -> str:
+    """The collection an RFC belongs to (`cached_rfcs.collection_id`). Falls back
+    to the default collection when the slug isn't cached. Mirrors
+    `project_of_rfc`'s first-match semantics; a slug shared across collections is
+    a known routing ambiguity (the RFC-grain helpers take a bare slug) resolved
+    by the collection-qualified routes in later slices."""
+    row = db.conn().execute(
+        "SELECT collection_id FROM cached_rfcs WHERE slug = ?", (rfc_slug,)
+    ).fetchone()
+    if row is None or not row["collection_id"]:
+        return collections_mod.DEFAULT_COLLECTION_ID
+    return row["collection_id"]
+
+
+def is_project_superuser(user: SessionUser | None, project_id: str) -> bool:
+    """Maximal authority within a project: a deployment owner/admin (superuser
+    in every project, §22.7) or an explicit `project_admin` (§22.6). Both
+    subsume the per-RFC owners/arbiters tier."""
+    if user is None:
+        return False
+    if user.role in _DEPLOYMENT_SUPERUSER_ROLES:
+        return True
+    return project_member_role(user, project_id) == "project_admin"
+
+
+def can_read_project(user: SessionUser | None, project_id: str) -> bool:
+    """The §22.5 visibility gate at the project grain. `public`/`unlisted` are
+    readable by anyone (anonymous included — `unlisted` is link-only but the link
+    still reads); `gated` is readable only by a deployment owner/admin or a
+    holder of any scope grant reaching the project — a global grant, a project
+    grant, or membership at *any* collection within it (seeing a collection
+    implies seeing its project). Used as the subtractive read gate (a gated
+    project's entries 404 to non-members)."""
+    vis = project_visibility(project_id)
+    if vis in ("public", "unlisted"):
+        return True
+    # gated — scope-role holders + superusers only, subject to the §6 floor.
+    if user is None or user.permission_state != "granted":
+        return False
+    if user.role in _DEPLOYMENT_SUPERUSER_ROLES:
+        return True
+    row = db.conn().execute(
+        "SELECT 1 FROM memberships m WHERE m.user_id = ? AND ("
+        "      m.scope_type = 'global'"
+        "   OR (m.scope_type = 'project' AND m.scope_id = ?)"
+        "   OR (m.scope_type = 'collection' AND m.scope_id IN "
+        "        (SELECT id FROM collections WHERE project_id = ?))) LIMIT 1",
+        (user.user_id, project_id, project_id),
+    ).fetchone()
+    return row is not None
+
+
+def require_project_readable(user: SessionUser | None, project_id: str) -> None:
+    """Raise 404 when the project is not readable by this viewer (§22.5: a
+    gated project is invisible to non-members — indistinguishable from absent,
+    so the shape matches an unknown slug)."""
+    if not can_read_project(user, project_id):
+        raise HTTPException(status_code=404, detail="RFC not found")
+
+
+def _has_write_baseline(user: SessionUser | None, project_id: str) -> bool:
+    """The implicit-on-public write baseline: a granted deployment
+    `contributor` on a `public` project carries the pre-multi-project
+    write standing (still subject to per-RFC curation). Deployment
+    owner/admin are handled by `is_project_superuser`; on gated/unlisted a
+    contributor has no baseline and needs an explicit project role."""
+    if user is None or user.permission_state != "granted":
+        return False
+    return user.role == "contributor" and project_visibility(project_id) == "public"
+
+
+def can_contribute_in_project(user: SessionUser | None, project_id: str) -> bool:
+    """May the user contribute *new* content to the project (propose an entry)
+    — the project-level (not RFC-specific) contribute standing. The union of
+    the override grants (superuser / explicit project_contributor) and the
+    implicit-public baseline, subject to the visibility gate."""
+    if user is None or user.permission_state != "granted":
+        return False
+    if not can_read_project(user, project_id):
+        return False
+    if is_project_superuser(user, project_id):
+        return True
+    if project_member_role(user, project_id) == "project_contributor":
+        return True
+    return _has_write_baseline(user, project_id)
+
+
+def can_discuss_in_project(user: SessionUser | None, project_id: str) -> bool:
+    """May the user participate in discussion in the project at all — the
+    project-level discuss standing (project_viewer ⊇ discussant, §22.7).
+    A superset of `can_contribute_in_project` (a contributor can discuss)."""
+    if user is None or user.permission_state != "granted":
+        return False
+    if not can_read_project(user, project_id):
+        return False
+    if is_project_superuser(user, project_id):
+        return True
+    if project_member_role(user, project_id) in ("project_viewer", "project_contributor"):
+        return True
+    return _has_write_baseline(user, project_id)
+
+
+def visible_project_ids(user: SessionUser | None) -> list[str]:
+    """Project ids whose entries may surface in a listing for this viewer — the
+    §22.5 read gate applied to the catalog/idea lists. (The directory's
+    `unlisted`-omission and the per-project routing are M3 concerns; for the M2
+    listing filter we include every project the viewer can read.)"""
+    rows = db.conn().execute("SELECT id FROM projects").fetchall()
+    return [r["id"] for r in rows if can_read_project(user, r["id"])]
+
+
+# ===========================================================================
+# §22 three-tier — S3. The four-layer scope-role resolver (§B.2) and the
+# collection-grain visibility gate.
+#
+# A grant attaches the unified role {owner, contributor} at a scope: global,
+# project, or collection (§B.1). Grants inherit downward, are additive, and
+# admit no negative override (§B.2). Effective authority over a *collection* is
+# the most-permissive union of the layers reaching it:
+#
+#     global   (users.role owner/admin  ∪  memberships scope_type='global')
+#   ∪ project  (memberships scope_type='project'    at the collection's project)
+#   ∪ collection (memberships scope_type='collection' at the collection)
+#
+# minus the §22.5 visibility gate and §6.2 write-mute (subtractive, as today).
+# Per-entry authority (owners / arbiters / rfc_collaborators) is a distinct,
+# finer layer the RFC-grain helpers union in beneath collection.
+#
+# OPERATOR DECISIONS (S3, session 0076):
+#  * scope-role-primary — a plain granted account (users.role 'contributor', no
+#    membership) is a granted *account*, not a write-everywhere global role.
+#    Write standing comes from an explicit scope grant; the lone exception is the
+#    grandfathered implicit-public baseline below.
+#  * grandfathered baseline — the migration-seeded `default` collection keeps the
+#    pre-three-tier implicit-on-public write baseline (a granted deployment
+#    contributor may propose while it is public), so the N=1 deployment (§22.13)
+#    loses no capability. Every *explicitly-created* collection requires an
+#    explicit scope grant to write.
+#  * hidden-from-public — a `gated` collection is invisible to the public (404,
+#    omitted from the directory) yet visible to any scope-role holder reaching it
+#    (collection/project/global). A collection's visibility may be set only as
+#    strict or stricter than its project's (the rank ordering below).
+# ===========================================================================
+
+# The global scope is a single tier per deployment; its grant rows use this
+# sentinel scope_id (migration 030).
+GLOBAL_SCOPE_ID = "*"
+
+# §22.5 visibility strictness on the public-exposure axis: `public` is least
+# strict, `gated` most strict. A collection may narrow its project's visibility
+# but never widen it (`rank(collection) >= rank(project)`).
+_VISIBILITY_RANK = {"public": 0, "unlisted": 1, "gated": 2}
+
+
+def visibility_rank(visibility: str | None) -> int:
+    """The strictness rank of a §22.5 visibility (higher = stricter). An unknown
+    value reads as the strictest (`gated`) — the safe default."""
+    return _VISIBILITY_RANK.get(visibility or "", _VISIBILITY_RANK["gated"])
+
+
+def effective_scope_role(user: SessionUser | None, collection_id: str) -> str | None:
+    """The most-permissive unified role ({'owner','contributor'}) the user holds
+    over `collection_id`, folding §B.2's global → project → collection layers.
+    Returns None when no scope grant reaches the collection. 'owner' outranks
+    'contributor'; there is no negative override (a parent grant is never
+    subtracted by a child). Subject to the §6 admission floor."""
+    if user is None or user.permission_state != "granted":
+        return None
+    # Global tier — a deployment owner/admin is a global Owner (§B.1).
+    if user.role in _DEPLOYMENT_SUPERUSER_ROLES:
+        return "owner"
+    pid = collections_mod.project_of_collection(collection_id)
+    row = db.conn().execute(
+        "SELECT role FROM memberships "
+        "WHERE user_id = ? AND ("
+        "      scope_type = 'global'"
+        "   OR (scope_type = 'project' AND scope_id = ?)"
+        "   OR (scope_type = 'collection' AND scope_id = ?)) "
+        "ORDER BY CASE role WHEN 'owner' THEN 0 ELSE 1 END LIMIT 1",
+        (user.user_id, pid, collection_id),
+    ).fetchone()
+    return row["role"] if row else None
+
+
+def collection_visibility(collection_id: str) -> str:
+    """The collection's own §22.5 visibility. A missing row reads as 'gated' —
+    an unknown collection is invisible rather than open."""
+    row = db.conn().execute(
+        "SELECT visibility FROM collections WHERE id = ?", (collection_id,)
+    ).fetchone()
+    if row is None or not row["visibility"]:
+        return "gated"
+    return row["visibility"]
+
+
+def effective_collection_visibility(collection_id: str) -> str:
+    """The stricter of the collection's own visibility and its project's (§22.5
+    'both gates'). A collection is constrained to be ≥ its project in strictness,
+    but we max() defensively so a misconfigured looser collection can never widen
+    its project's gate."""
+    cvis = collection_visibility(collection_id)
+    pid = collections_mod.project_of_collection(collection_id)
+    pvis = project_visibility(pid) if pid else "gated"
+    return cvis if visibility_rank(cvis) >= visibility_rank(pvis) else pvis
+
+
+def can_read_collection(user: SessionUser | None, collection_id: str) -> bool:
+    """§22.5 read/existence gate at the collection grain. `public`/`unlisted`
+    read by anyone (anonymous included — `unlisted` is link-only but the link
+    reads); `gated` ("hidden from public existence") reads only for a scope-role
+    holder over the collection (collection/project/global) or a deployment
+    owner/admin. The subtractive read gate — a gated collection 404s a
+    non-holder, indistinguishable from absent."""
+    vis = effective_collection_visibility(collection_id)
+    if vis in ("public", "unlisted"):
+        return True
+    if user is None or user.permission_state != "granted":
+        return False
+    return effective_scope_role(user, collection_id) is not None
+
+
+def require_collection_readable(user: SessionUser | None, collection_id: str) -> None:
+    """Raise 404 when the collection is not readable by this viewer (§22.5: a
+    hidden/gated collection is invisible to non-holders — the shape matches an
+    unknown collection)."""
+    if not can_read_collection(user, collection_id):
+        raise HTTPException(status_code=404, detail="Not found")
+
+
+def is_collection_superuser(user: SessionUser | None, collection_id: str) -> bool:
+    """Maximal authority over a collection: an effective scope role of 'owner'
+    reaching it (a collection Owner, a project Owner of its project, a global
+    Owner, or a deployment owner/admin). Subsumes the per-entry owners/arbiters
+    tier within the collection."""
+    return effective_scope_role(user, collection_id) == "owner"
+
+
+def _has_collection_write_baseline(user: SessionUser | None, collection_id: str) -> bool:
+    """The grandfathered implicit-on-public write baseline, narrowed to the
+    migration-seeded `default` collection (§22.13 N=1 case). A granted deployment
+    `contributor` keeps its pre-three-tier write standing on the default
+    collection while its effective visibility is public; every explicitly-created
+    collection requires an explicit scope grant (S3 operator decision)."""
+    if user is None or user.permission_state != "granted":
+        return False
+    if collection_id != collections_mod.DEFAULT_COLLECTION_ID:
+        return False
+    return user.role == "contributor" and effective_collection_visibility(collection_id) == "public"
+
+
+def can_contribute_in_collection(user: SessionUser | None, collection_id: str) -> bool:
+    """May the user contribute *new* content to the collection (propose an entry)
+    — the collection-level contribute standing. The union of the scope-role grant
+    (owner/contributor reaching the collection) and the grandfathered default
+    baseline, subject to the visibility read gate."""
+    if user is None or user.permission_state != "granted":
+        return False
+    if not can_read_collection(user, collection_id):
+        return False
+    if effective_scope_role(user, collection_id) is not None:
+        return True
+    return _has_collection_write_baseline(user, collection_id)
+
+
+def can_discuss_in_collection(user: SessionUser | None, collection_id: str) -> bool:
+    """May the user participate in discussion in the collection — the
+    collection-level discuss standing. A superset of contribute for this pass
+    (the read-only viewer tier is deferred, §B.3), so it mirrors
+    `can_contribute_in_collection`."""
+    return can_contribute_in_collection(user, collection_id)
+
+
+def can_create_collection(user: SessionUser | None, project_id: str) -> bool:
+    """May the user create a new collection in this project (§B.1)? Creating a
+    collection is a *project-level* action: a deployment owner/admin, or any
+    holder of a project-scope or global-scope grant (Owner OR RFC Contributor —
+    'anyone at the project level with permission to create a collection'). A
+    *collection*-scope grant cannot create sibling collections."""
+    if user is None or user.permission_state != "granted":
+        return False
+    if user.role in _DEPLOYMENT_SUPERUSER_ROLES:
+        return True
+    row = db.conn().execute(
+        "SELECT 1 FROM memberships "
+        "WHERE user_id = ? AND ("
+        "      scope_type = 'global'"
+        "   OR (scope_type = 'project' AND scope_id = ?)) LIMIT 1",
+        (user.user_id, project_id),
+    ).fetchone()
+    return row is not None
+
+
+# v0.16.0 (roadmap item #12): per-RFC membership helpers.
+#
+# These don't replace `require_contributor` — they layer on top of it for
+# endpoints that an RFC's owner can selectively open up. The "discussion"
+# and "PR" write surfaces consult `is_rfc_writer(...)` / `is_rfc_discussant(...)`
+# to admit users who are either platform-privileged (admin, RFC owner)
+# OR who hold an explicit invitation-accepted per-RFC role.
+#
+# The platform gate still fires first: a user whose
+# `permission_state != 'granted'` cannot write anywhere, invitation or
+# not. v0.16.0 doesn't loosen that — a per-RFC invitation is additive
+# *within* the granted-platform-user population. (Accepting an
+# invitation as a pending user surfaces in the admin-page hook per
+# the roadmap text; the platform grant remains the admin's decision.)
+
+
+def _rfc_owners_set(rfc_slug: str) -> set[str]:
+    """The gitea_logins named in the RFC's frontmatter owners array.
+
+    Read from `cached_rfcs.owners_json`. Returns an empty set if the RFC
+    isn't cached (the caller's earlier `_require_rfc_readable` will
+    already have rejected that case in practice).
+    """
+    import json as _json
+    row = db.conn().execute(
+        "SELECT owners_json FROM cached_rfcs WHERE slug = ?", (rfc_slug,),
+    ).fetchone()
+    if row is None:
+        return set()
+    try:
+        return set(_json.loads(row["owners_json"] or "[]"))
+    except Exception:
+        return set()
+
+
+def is_rfc_owner(user: SessionUser | None, rfc_slug: str) -> bool:
+    """True iff the user is named in the RFC's frontmatter `owners`
+    list. The platform-level admin/owner check is separate; per §6.1 an
+    app admin/owner has all per-RFC capabilities by construction, but
+    this predicate is intentionally narrow — it answers "is this
+    person on the RFC's owners line?" and nothing more.
+    """
+    if user is None:
+        return False
+    return user.gitea_login in _rfc_owners_set(rfc_slug)
+
+
+def is_rfc_collaborator(user: SessionUser | None, rfc_slug: str, *, role_in_rfc: str | None = None) -> bool:
+    """True iff the user has an accepted per-RFC collaborator row.
+
+    `role_in_rfc`:
+      * None — any role qualifies (the discussion-write check uses this
+        shape: contributor strictly includes discussant).
+      * 'contributor' — only the contributor role qualifies (the PR-write
+        check uses this shape).
+      * 'discussant' — only the discussant role qualifies (not used by
+        v0.16.0 endpoints; included for symmetry).
+    """
+    if user is None:
+        return False
+    if role_in_rfc is None:
+        row = db.conn().execute(
+            "SELECT 1 FROM rfc_collaborators WHERE rfc_slug = ? AND user_id = ? LIMIT 1",
+            (rfc_slug, user.user_id),
+        ).fetchone()
+        return row is not None
+    row = db.conn().execute(
+        "SELECT 1 FROM rfc_collaborators WHERE rfc_slug = ? AND user_id = ? AND role_in_rfc = ? LIMIT 1",
+        (rfc_slug, user.user_id, role_in_rfc),
+    ).fetchone()
+    return row is not None
+
+
+def can_discuss_rfc(user: SessionUser | None, rfc_slug: str) -> bool:
+    """v0.16.0 — admit to PR-less discussion writes on this RFC.
+
+    True if ANY of:
+      * platform admin/owner (the §6.1 maximal-capability path),
+      * the RFC has no frontmatter owners yet (the gate is open
+        until an owner exists to set it — relevant for super-drafts
+        pre-§13.1 claim),
+      * RFC owner (frontmatter `owners` membership),
+      * accepted per-RFC collaborator at any role (contributor strictly
+        includes discussant).
+
+    Returns False for anonymous viewers and for users whose
+    `permission_state != 'granted'` — the platform-level gate must hold
+    before any per-RFC layer can apply. The platform gate is also
+    enforced earlier in the request via `require_contributor`; the
+    helper here is defensive so callers that compose it with
+    `current_user` directly still respect the gate.
+    """
+    if user is None:
+        return False
+    if user.permission_state != "granted":
+        return False
+    cid = collection_of_rfc(rfc_slug)
+    # §22.5 visibility gate is subtractive (§22.7) — no capability in a
+    # collection the viewer cannot even read.
+    if not can_read_collection(user, cid):
+        return False
+    # §B.2 union, scope-role grants first — these bypass per-RFC curation (a
+    # collection/project/global Owner or RFC Contributor ⊇ discussant).
+    if effective_scope_role(user, cid) is not None:
+        return True
+    # per-RFC authority (union term).
+    owners = _rfc_owners_set(rfc_slug)
+    if user.gitea_login in owners:
+        return True
+    if is_rfc_collaborator(user, rfc_slug, role_in_rfc=None):
+        return True
+    # grandfathered implicit-public baseline (curation preserved): on the default
+    # collection a granted deployment contributor may discuss only while the RFC
+    # is unclaimed. The first §13.1 claim engages the per-RFC gate, mirroring the
+    # pre-multi-project v0.16.0 contract.
+    if not owners and _has_collection_write_baseline(user, cid):
+        return True
+    return False
+
+
+def can_contribute_to_rfc(user: SessionUser | None, rfc_slug: str) -> bool:
+    """v0.16.0 — admit to PR-shaped writes on this RFC.
+
+    True if ANY of:
+      * platform admin/owner,
+      * the RFC has no frontmatter owners yet (gate open until an
+        owner exists),
+      * RFC owner,
+      * accepted per-RFC collaborator at role 'contributor' (a
+        'discussant' row is NOT sufficient — PRs are the
+        higher-privilege surface).
+
+    Same `permission_state` and anonymous-viewer refusals as
+    `can_discuss_rfc`.
+    """
+    if user is None:
+        return False
+    if user.permission_state != "granted":
+        return False
+    cid = collection_of_rfc(rfc_slug)
+    if not can_read_collection(user, cid):
+        return False
+    # §B.2 union, scope-role grants first (a collection/project/global RFC
+    # Contributor ⊇ rfc_collaborators(contributor); an Owner ⊇ all).
+    if effective_scope_role(user, cid) is not None:
+        return True
+    # per-RFC authority (union term). A 'discussant' row is NOT sufficient —
+    # PRs are the higher-privilege surface.
+    owners = _rfc_owners_set(rfc_slug)
+    if user.gitea_login in owners:
+        return True
+    if is_rfc_collaborator(user, rfc_slug, role_in_rfc="contributor"):
+        return True
+    # grandfathered implicit-public baseline (curation preserved): until an owner
+    # exists, a granted deployment contributor on the public default collection
+    # may contribute.
+    if not owners and _has_collection_write_baseline(user, cid):
+        return True
+    return False
+
+
+def can_invite_to_rfc(user: SessionUser | None, rfc_slug: str) -> bool:
+    """v0.16.0 — only RFC owners (frontmatter) and platform admin/owner
+    can issue invitations. Per-RFC collaborators do not get the
+    invite-others power; that stays with the RFC's owner."""
+    if user is None:
+        return False
+    if user.permission_state != "granted":
+        return False
+    cid = collection_of_rfc(rfc_slug)
+    if not can_read_collection(user, cid):
+        return False
+    # An Owner reaching the collection (collection/project/global Owner, or a
+    # deployment owner/admin) may invite; otherwise only the RFC's frontmatter
+    # owner. Per-RFC collaborators and the baseline do not get the invite power.
+    if is_collection_superuser(user, cid):
+        return True
+    return is_rfc_owner(user, rfc_slug)
+
+
 def new_state() -> str:
     return secrets.token_urlsafe(16)

backend/app/bot.py

@@ -27,7 +27,7 @@ import json
 import logging
 from dataclasses import dataclass
 
-from . import db, notify
+from . import db, entry as entry_mod, notify
 from .gitea import Gitea, GiteaError
 
 log = logging.getLogger(__name__)
@@ -163,6 +163,41 @@ class Bot:
     def __init__(self, gitea: Gitea):
         self._gitea = gitea
 
+    # ----- Content repo: collection structure (§22 S2) -----
+
+    async def create_collection(
+        self,
+        actor: Actor,
+        *,
+        org: str,
+        content_repo: str,
+        collection_id: str,
+        manifest_yaml: str,
+    ) -> dict:
+        """§22 S2: commit `<collection_id>/.collection.yaml` to the content
+        repo's main. A structural admin action — committed straight to main (no
+        PR), like the registry config it feeds; the registry mirror then upserts
+        the collections row (§22.2 keeps the registry the source of truth). Logs
+        an audit row for the §6.5 trail."""
+        path = f"{collection_id}/.collection.yaml"
+        created = await self._gitea.create_file(
+            org,
+            content_repo,
+            path,
+            content=manifest_yaml,
+            message=_stamp_single(f"chore: create collection {collection_id}", actor),
+            branch="main",
+            author_name=actor.display_name,
+            author_email=actor.email or f"{actor.gitea_login}@users.noreply",
+        )
+        _log(
+            actor,
+            "create_collection",
+            bot_commit_sha=created.get("commit", {}).get("sha"),
+            details={"collection_id": collection_id, "repo": content_repo},
+        )
+        return created
+
     # ----- Meta repo: idea PRs (§9.1 / §9.2) -----
 
     async def open_idea_pr(
@@ -175,12 +210,16 @@ class Bot:
         file_contents: str,
         pr_title: str,
         pr_description: str,
+        rfcs_dir: str = "rfcs",
     ) -> dict:
-        """Per §9.1: open a meta-repo PR adding one file under rfcs/.
+        """Per §9.1: open a meta-repo PR adding one file under `<rfcs_dir>/`.
 
         One file per PR keeps idea submissions atomic and conflict-free.
         The PR title and the file-add commit subject share §9.2's fixed
-        pattern; callers compose `pr_title` as `Propose: <Title>`.
+        pattern; callers compose `pr_title` as `Propose: <Title>`. §22 S2:
+        `rfcs_dir` carries the target collection's `<subfolder>/rfcs` so a
+        propose into a named collection writes under its subfolder; it
+        defaults to `rfcs` (the default collection / shipped behaviour).
         """
         branch = f"propose/{slug}"
         await self._gitea.create_branch(org, meta_repo, branch, from_branch="main")
@@ -189,7 +228,7 @@ class Bot:
         created = await self._gitea.create_file(
             org,
             meta_repo,
-            f"rfcs/{slug}.md",
+            f"{rfcs_dir}/{slug}.md",
             content=file_contents,
             message=commit_message,
             branch=branch,
@@ -695,111 +734,7 @@ class Bot:
         )
         return sha
 
-    # ----- §13 graduation: per-step primitives and rollback inverses -----
-
-    async def create_rfc_repo_for_graduation(
-        self,
-        actor: Actor,
-        *,
-        org: str,
-        repo_name: str,
-        slug: str,
-        title: str,
-    ) -> dict:
-        """§13.3 step 1: create the per-RFC repo.
-
-        Empty repo (no auto-init) — `seed_graduated_rfc` writes the first
-        commit on `main`. Returns the Gitea repo payload."""
-        repo = await self._gitea.create_org_repo(
-            org, repo_name, description=f"RFC: {title}"
-        )
-        _log(
-            actor,
-            "graduate_repo_create",
-            rfc_slug=slug,
-            details={"repo": f"{org}/{repo_name}", "title": title},
-        )
-        return repo
-
-    async def seed_graduated_rfc(
-        self,
-        actor: Actor,
-        *,
-        org: str,
-        repo_name: str,
-        slug: str,
-        title: str,
-        rfc_body: str,
-        rfc_id: str,
-        meta_full: str,
-        meta_path: str,
-        owners: list[str],
-        arbiters: list[str],
-        tags: list[str],
-    ) -> str:
-        """§13.3 step 2: seed RFC.md, README.md, .rfc/metadata.yaml on the
-        new repo's `main`. Three create_file calls; one audit row.
-
-        Returns the final commit sha on main.
-        """
-        import yaml as _yaml
-
-        ae = actor.email or f"{actor.gitea_login}@users.noreply"
-        # 2a) RFC.md — the document. The super-draft's body is migrated
-        # verbatim per §13.3; if the body is empty we seed a minimal
-        # placeholder so the editor has something to render on first open.
-        body = rfc_body.strip() + "\n" if rfc_body.strip() else (
-            f"# {title}\n\n*RFC.md to be filled in — the super-draft graduated with an empty body.*\n"
-        )
-        rfc_msg = _stamp_single(f"Seed RFC.md from super-draft {slug}", actor)
-        rfc_result = await self._gitea.create_file(
-            org, repo_name, "RFC.md",
-            content=body, message=rfc_msg, branch="main",
-            author_name=actor.display_name, author_email=ae,
-        )
-        # 2b) README.md — header pointing back at the meta-repo entry.
-        readme = (
-            f"# {rfc_id} — {title}\n\n"
-            f"This repository carries the canonical text of {rfc_id}.\n"
-            f"The meta-repo entry is `{meta_path}` in `{meta_full}`.\n\n"
-            f"The RFC body is in `RFC.md`. Contributions go through the\n"
-            f"app's §8 RFC view — open a branch, propose changes, land a PR.\n"
-        )
-        readme_msg = _stamp_single(f"Seed README.md for {rfc_id}", actor)
-        await self._gitea.create_file(
-            org, repo_name, "README.md",
-            content=readme, message=readme_msg, branch="main",
-            author_name=actor.display_name, author_email=ae,
-        )
-        # 2c) .rfc/metadata.yaml — mirror of meta-repo frontmatter for
-        # future tooling (linting, automation, CI lookups).
-        meta_yaml = _yaml.safe_dump(
-            {
-                "slug": slug, "title": title, "id": rfc_id,
-                "owners": owners, "arbiters": arbiters, "tags": list(tags),
-            },
-            sort_keys=False,
-        )
-        meta_msg = _stamp_single(f"Seed .rfc/metadata.yaml for {rfc_id}", actor)
-        meta_result = await self._gitea.create_file(
-            org, repo_name, ".rfc/metadata.yaml",
-            content=meta_yaml, message=meta_msg, branch="main",
-            author_name=actor.display_name, author_email=ae,
-        )
-        last_sha = (
-            meta_result.get("commit", {}).get("sha")
-            or rfc_result.get("commit", {}).get("sha")
-            or ""
-        )
-        _log(
-            actor,
-            "graduate_repo_seed",
-            rfc_slug=slug,
-            branch_name="main",
-            bot_commit_sha=last_sha,
-            details={"repo": f"{org}/{repo_name}", "rfc_id": rfc_id},
-        )
-        return last_sha
+    # ----- §13 graduation (meta-only): open + merge the flip PR -----
 
     async def open_graduation_pr(
         self,
@@ -810,12 +745,15 @@ class Bot:
         slug: str,
         new_file_contents: str,
         prior_sha: str,
-        rfc_id: str,
-        repo_full: str,
+        rfc_id: str | None,
         owners: list[str],
     ) -> dict:
-        """§13.3 step 3: open a PR against the meta repo that strips the
-        super-draft body and fills graduation frontmatter fields. Branch
+        """§13.3 (meta-only): open a PR against the meta repo that flips the
+        entry's frontmatter to `state: active` with the graduation stamps
+        and — **optionally** — the integer `id`, **keeping the body
+        unchanged** (§1 meta-only topology; no repo is created and no body
+        is stripped). When `rfc_id` is None the entry graduates without a
+        number (id stays null, slug is canonical per §2.3, §13.2). Branch
         name uses the `graduate-<slug>-<6hex>` shape — dash-separated like
         the other meta-repo branches per the §19.2 path-routing candidate.
         """
@@ -824,7 +762,7 @@ class Bot:
         branch = f"graduate-{slug}-{secrets.token_hex(3)}"
         await self._gitea.create_branch(org, meta_repo, branch, from_branch="main")
         ae = actor.email or f"{actor.gitea_login}@users.noreply"
-        commit_subject = f"Graduate {slug} → {rfc_id}"
+        commit_subject = f"Graduate {slug} → {rfc_id}" if rfc_id else f"Graduate {slug} (no number)"
         commit_message = _stamp_single(commit_subject, actor)
         result = await self._gitea.update_file(
             org, meta_repo, f"rfcs/{slug}.md",
@@ -839,16 +777,17 @@ class Bot:
             or result.get("content", {}).get("sha")
             or ""
         )
-        pr_title = f"Graduate {slug} → {rfc_id}"
+        pr_title = f"Graduate {slug} → {rfc_id}" if rfc_id else f"Graduate {slug} (no number)"
         owners_str = ", ".join(owners) if owners else "(none)"
+        id_line = f"- ID: `{rfc_id}`\n" if rfc_id else "- ID: (none — identified by slug)\n"
         pr_body_text = (
             f"Graduates super-draft `{slug}` to active.\n\n"
-            f"- ID: `{rfc_id}`\n"
-            f"- Repo: `{repo_full}`\n"
+            f"{id_line}"
             f"- Owners: {owners_str}\n\n"
-            f"The meta-repo entry becomes frontmatter-only; the canonical body\n"
-            f"moves to `RFC.md` in the new repo. The graduation sequence is\n"
-            f"transactional per §13.3."
+            f"This is an in-place state flip per the meta-only topology\n"
+            f"(SPEC §1, §13.3): the entry `rfcs/{slug}.md` keeps its body and\n"
+            f"stays in the meta repo. Only the frontmatter changes — `state`,\n"
+            f"`id`, and the graduation stamps."
         )
         _subject, pr_body = _stamp("", pr_body_text, actor)
         pr = await self._gitea.create_pull(
@@ -862,7 +801,7 @@ class Bot:
             branch_name=branch,
             pr_number=pr["number"],
             bot_commit_sha=commit_sha,
-            details={"pr_title": pr_title, "rfc_id": rfc_id, "repo": repo_full},
+            details={"pr_title": pr_title, "rfc_id": rfc_id},
         )
         return pr
 
@@ -875,7 +814,7 @@ class Bot:
         pr_number: int,
         head_branch: str,
         slug: str,
-        rfc_id: str,
+        rfc_id: str | None,
     ) -> None:
         """§13.3 step 4: auto-merge the graduation PR with the admin as
         merge actor. Distinct action_kind so the audit log carries the
@@ -891,7 +830,7 @@ class Bot:
         reports the transient state (belt-and-suspenders against the same
         race appearing in a different shape).
         """
-        subject = f"Graduate {slug} → {rfc_id}"
+        subject = f"Graduate {slug} → {rfc_id}" if rfc_id else f"Graduate {slug} (no number)"
         body = _trailer(actor)
 
         try:
@@ -912,27 +851,106 @@ class Bot:
             details={"rfc_id": rfc_id},
         )
 
-    # ----- §13.3 rollback inverses -----
+    # ----- §13.7 retire / un-retire: open + merge a state-flip PR -----
 
-    async def delete_rfc_repo(
+    async def open_retire_flip_pr(
         self,
         actor: Actor,
         *,
         org: str,
-        repo_name: str,
+        meta_repo: str,
         slug: str,
-        reason: str,
-    ) -> None:
-        """Undo of `create_rfc_repo_for_graduation`. Records `graduate_repo_delete`
-        in the audit log with the rollback reason so the §13.3 stack's
-        rendered failure surface can be reconstructed from `actions`."""
-        await self._gitea.delete_repo(org, repo_name)
+        new_file_contents: str,
+        prior_sha: str,
+        verb: str,
+        target_state: str,
+    ) -> dict:
+        """§13.7: open a PR flipping `rfcs/<slug>.md` to `state:
+        <target_state>` — for retire (`verb='retire'`, target `retired`)
+        or un-retire (`verb='unretire'`, target the restored prior state).
+        Only the frontmatter `state` changes; the body and every other
+        field (including the integer `id`) are kept, so an un-retire
+        restores the entry exactly. Branch shape mirrors graduation's
+        `<verb>-<slug>-<6hex>`.
+        """
+        import secrets
+
+        branch = f"{verb}-{slug}-{secrets.token_hex(3)}"
+        await self._gitea.create_branch(org, meta_repo, branch, from_branch="main")
+        ae = actor.email or f"{actor.gitea_login}@users.noreply"
+        verb_title = "Retire" if verb == "retire" else "Un-retire"
+        commit_subject = f"{verb_title} {slug}"
+        commit_message = _stamp_single(commit_subject, actor)
+        result = await self._gitea.update_file(
+            org, meta_repo, f"rfcs/{slug}.md",
+            content=new_file_contents,
+            sha=prior_sha,
+            message=commit_message,
+            branch=branch,
+            author_name=actor.display_name, author_email=ae,
+        )
+        commit_sha = (
+            result.get("commit", {}).get("sha")
+            or result.get("content", {}).get("sha")
+            or ""
+        )
+        pr_title = f"{verb_title} {slug}"
+        pr_body_text = (
+            f"{verb_title}s `{slug}` (state → `{target_state}`).\n\n"
+            f"This is an in-place frontmatter flip per SPEC §13.7 — the\n"
+            f"entry `rfcs/{slug}.md` keeps its body and every other field;\n"
+            f"only `state` changes."
+        )
+        _subject, pr_body = _stamp("", pr_body_text, actor)
+        pr = await self._gitea.create_pull(
+            org, meta_repo,
+            title=pr_title, body=pr_body, head=branch, base="main",
+        )
         _log(
             actor,
-            "graduate_repo_delete",
+            f"{verb}_pr_open",
             rfc_slug=slug,
-            details={"repo": f"{org}/{repo_name}", "reason": reason},
+            branch_name=branch,
+            pr_number=pr["number"],
+            bot_commit_sha=commit_sha,
+            details={"pr_title": pr_title, "target_state": target_state},
         )
+        return pr
+
+    async def merge_retire_flip_pr(
+        self,
+        actor: Actor,
+        *,
+        org: str,
+        meta_repo: str,
+        pr_number: int,
+        head_branch: str,
+        slug: str,
+        verb: str,
+    ) -> None:
+        """§13.7: auto-merge the retire / un-retire flip PR (same
+        mergeable-wait + retry shape as `merge_graduation_pr`)."""
+        verb_title = "Retire" if verb == "retire" else "Un-retire"
+        subject = f"{verb_title} {slug}"
+        body = _trailer(actor)
+        try:
+            await self._gitea.wait_for_mergeable(org, meta_repo, pr_number)
+        except TimeoutError as e:
+            raise GiteaError(409, str(e)) from e
+        await _merge_with_retry(
+            self._gitea, org, meta_repo, pr_number,
+            merge_message_title=subject, merge_message_body=body,
+        )
+        _log(
+            actor,
+            f"{verb}_pr_merge",
+            rfc_slug=slug,
+            branch_name=head_branch,
+            pr_number=pr_number,
+            details={},
+        )
+
+    # ----- §13.3 (meta-only): cleanup of an unmerged flip PR -----
 
     async def close_graduation_pr(
         self,
@@ -1090,6 +1108,54 @@ class Bot:
         )
         return pr
 
+    # ----- §22.4c: mark-reviewed (direct main write) -----
+
+    async def mark_entry_reviewed(
+        self,
+        actor: Actor,
+        *,
+        org: str,
+        meta_repo: str,
+        slug: str,
+        reviewed_by: str,
+        reviewed_at: str,
+    ) -> None:
+        """Clear §22.4c unreviewed on an active entry by rewriting its
+        frontmatter on main. Stamps the commit with the §6.5 On-behalf-of
+        trailer and writes an actions-log row, mirroring the graduation
+        stamp's bot-write shape."""
+        path = f"rfcs/{slug}.md"
+        result = await self._gitea.read_file(org, meta_repo, path, ref="main")
+        if result is None:
+            raise GiteaError(404, f"{path} not found")
+        text, sha = result
+        e = entry_mod.parse(text)
+        e.unreviewed = False
+        e.reviewed_at = reviewed_at
+        e.reviewed_by = reviewed_by
+        commit_message = _stamp_single(f"Mark {slug} reviewed", actor)
+        result = await self._gitea.update_file(
+            org, meta_repo, path,
+            content=entry_mod.serialize(e),
+            sha=sha,
+            message=commit_message,
+            branch="main",
+            author_name=actor.display_name,
+            author_email=actor.email or f"{actor.gitea_login}@users.noreply",
+        )
+        commit_sha = (
+            result.get("commit", {}).get("sha")
+            or result.get("content", {}).get("sha")
+            or ""
+        )
+        _log(
+            actor,
+            "mark_reviewed",
+            rfc_slug=slug,
+            bot_commit_sha=commit_sha,
+            details={"reviewed_by": reviewed_by, "reviewed_at": reviewed_at},
+        )
+
     # ----- Per-RFC repo: seeding (test/dev fixtures, future graduation) -----
 
     async def ensure_rfc_repo_seed(

backend/app/cache.py

@@ -27,7 +27,7 @@ import asyncio
 import json
 import logging
 
-from . import db, entry as entry_mod
+from . import db, entry as entry_mod, projects as projects_mod, registry as registry_mod
 from .config import Config
 from .gitea import Gitea, GiteaError
 
@@ -35,16 +35,46 @@ log = logging.getLogger(__name__)
 
 
 async def refresh_meta_repo(config: Config, gitea: Gitea) -> None:
-    """Re-read rfcs/ on the meta repo and reconcile cached_rfcs.
+    """Re-read rfcs/ on every project's content repo and reconcile cached_rfcs.
 
-    Idempotent. Safe to call on every meta-repo webhook and on every
-    reconciler sweep.
+    §22 (Plan B): a deployment has N projects (§22.1), each with its own
+    content_repo (§22.3). Mirror each into cached_rfcs stamped with that
+    project's id, so a second project's corpus renders under /p/<id>/. Idempotent;
+    safe on every content-repo webhook and reconciler sweep.
     """
-    org, repo = config.gitea_org, config.meta_repo
+    org = config.gitea_org
+    rows = db.conn().execute(
+        "SELECT id, content_repo FROM projects WHERE content_repo IS NOT NULL AND content_repo != ''"
+    ).fetchall()
+    if not rows:
+        log.warning("refresh_meta_repo: no projects with a content_repo yet; skipping")
+        return
+    for prow in rows:
+        await _refresh_project_corpus(org, prow["id"], prow["content_repo"], gitea)
+
+
+async def _refresh_project_corpus(org: str, project_id: str, repo: str, gitea: Gitea) -> None:
+    # §22 S2: the corpus grain is the collection. Mirror every collection of the
+    # project from its `<subfolder>/rfcs/` directory, keying cached_rfcs by the
+    # collection id. The default collection (subfolder '') reads `rfcs/` — the
+    # shipped path, unchanged. include_unlisted: the mirror serves every
+    # collection's content regardless of enumeration visibility.
+    from . import collections as collections_mod
+    for col in collections_mod.list_collections(project_id, include_unlisted=True):
+        await _refresh_collection_corpus(
+            org, project_id, repo, col["id"], col["subfolder"] or "", gitea
+        )
+
+
+async def _refresh_collection_corpus(
+    org: str, project_id: str, repo: str, collection_id: str, subfolder: str, gitea: Gitea
+) -> None:
+    rfcs_dir = f"{subfolder}/rfcs" if subfolder else "rfcs"
     try:
-        files = await gitea.list_dir(org, repo, "rfcs", ref="main")
+        files = await gitea.list_dir(org, repo, rfcs_dir, ref="main")
     except GiteaError as e:
-        log.warning("refresh_meta_repo: cannot list rfcs/: %s", e)
+        log.warning("refresh_meta_repo: %s/%s: cannot list %s: %s",
+                    project_id, collection_id, rfcs_dir, e)
         return
 
     seen_slugs: set[str] = set()
@@ -58,24 +88,31 @@ async def refresh_meta_repo(config: Config, gitea: Gitea) -> None:
         try:
             entry = entry_mod.parse(text)
         except Exception as parse_err:
-            log.warning("refresh_meta_repo: skipping %s: %s", f["path"], parse_err)
+            log.warning("refresh_meta_repo: %s/%s: skipping %s: %s",
+                        project_id, collection_id, f["path"], parse_err)
             continue
         if not entry.slug:
-            log.warning("refresh_meta_repo: skipping %s: missing slug", f["path"])
+            log.warning("refresh_meta_repo: %s/%s: skipping %s: missing slug",
+                        project_id, collection_id, f["path"])
             continue
         seen_slugs.add(entry.slug)
-        _upsert_cached_rfc(entry, body_sha=sha)
+        _upsert_cached_rfc(entry, body_sha=sha, collection_id=collection_id)
 
-    # Mark entries removed from the meta repo as withdrawn-without-trace.
-    # In practice the spec keeps withdrawn entries in rfcs/ as historical
-    # record (§3), so this branch fires only for entries deleted out of
-    # band. We leave the row but flag it for reconciler attention.
-    existing = {row["slug"] for row in db.conn().execute("SELECT slug FROM cached_rfcs")}
+    # Entries removed from a collection's rfcs/ — the spec keeps withdrawn entries
+    # as historical record (§3), so this fires only for out-of-band deletes;
+    # leave the row, scoped to this collection, for reconciler attention.
+    existing = {
+        row["slug"]
+        for row in db.conn().execute(
+            "SELECT slug FROM cached_rfcs WHERE collection_id = ?", (collection_id,)
+        )
+    }
     for missing in existing - seen_slugs:
-        log.info("refresh_meta_repo: %s no longer in rfcs/ — leaving cache row in place", missing)
+        log.info("refresh_meta_repo: %s/%s/%s no longer present — leaving cache row",
+                 project_id, collection_id, missing)
 
 
-def _upsert_cached_rfc(entry: entry_mod.Entry, body_sha: str) -> None:
+def _upsert_cached_rfc(entry: entry_mod.Entry, body_sha: str, collection_id: str = "default") -> None:
     # §6.6: models_json stays NULL when the frontmatter key is absent
     # (inherit operator universe) and '[]' for the explicit opt-out.
     models_json = json.dumps(entry.models) if entry.models is not None else None
@@ -87,9 +124,11 @@ def _upsert_cached_rfc(entry: entry_mod.Entry, body_sha: str) -> None:
         INSERT INTO cached_rfcs
             (slug, title, state, rfc_id, repo, proposed_by, proposed_at,
              graduated_at, graduated_by, owners_json, arbiters_json, tags_json,
-             models_json, funder_login, body, body_sha, last_entry_commit_at, updated_at)
-        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, datetime('now'), datetime('now'))
-        ON CONFLICT(slug) DO UPDATE SET
+             models_json, funder_login, body, body_sha,
+             unreviewed, reviewed_at, reviewed_by, collection_id,
+             last_entry_commit_at, updated_at)
+        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, datetime('now'), datetime('now'))
+        ON CONFLICT(collection_id, slug) DO UPDATE SET
             title = excluded.title,
             state = excluded.state,
             rfc_id = excluded.rfc_id,
@@ -105,6 +144,9 @@ def _upsert_cached_rfc(entry: entry_mod.Entry, body_sha: str) -> None:
             funder_login = excluded.funder_login,
             body = excluded.body,
             body_sha = excluded.body_sha,
+            unreviewed = excluded.unreviewed,
+            reviewed_at = excluded.reviewed_at,
+            reviewed_by = excluded.reviewed_by,
             last_entry_commit_at = datetime('now'),
             updated_at = datetime('now')
         """,
@@ -125,6 +167,10 @@ def _upsert_cached_rfc(entry: entry_mod.Entry, body_sha: str) -> None:
             funder_login,
             entry.body,
             body_sha,
+            1 if entry.unreviewed else 0,
+            entry.reviewed_at,
+            entry.reviewed_by,
+            collection_id,
         ),
     )
 
@@ -184,7 +230,7 @@ async def refresh_rfc_repo(config: Config, gitea: Gitea, slug: str) -> None:
             """
             INSERT INTO cached_branches (rfc_slug, branch_name, head_sha, state, last_commit_at)
             VALUES (?, ?, ?, 'open', ?)
-            ON CONFLICT(rfc_slug, branch_name) DO UPDATE SET
+            ON CONFLICT(collection_id, rfc_slug, branch_name) DO UPDATE SET
                 head_sha = excluded.head_sha,
                 state = CASE WHEN cached_branches.state = 'closed' THEN 'closed' ELSE 'open' END,
                 last_commit_at = excluded.last_commit_at
@@ -219,6 +265,19 @@ async def refresh_rfc_repo(config: Config, gitea: Gitea, slug: str) -> None:
         open_pulls, closed_pulls = [], []
     for pull in open_pulls + closed_pulls:
         head_branch = pull.get("head", {}).get("ref", "")
+        # Same deleted-branch recovery as refresh_meta_pulls: a merged-and-
+        # deleted PR's `head.ref` collapses to `refs/pull/<N>/head`. Here
+        # the slug is known (param), so state still updates correctly and
+        # no ghost forms — but blindly storing the sentinel would clobber
+        # the real branch name api_prs.py relies on as a fallback ref when
+        # the merge commit is gone. Recover it from the stored row.
+        if not head_branch or head_branch.startswith("refs/pull/"):
+            prior = db.conn().execute(
+                "SELECT head_branch FROM cached_prs WHERE repo = ? AND pr_number = ?",
+                (repo_full, pull["number"]),
+            ).fetchone()
+            if prior and prior["head_branch"]:
+                head_branch = prior["head_branch"]
         state = _state_from_pull(pull)
         gitea_opener = (pull.get("user") or {}).get("login") or ""
         opened_by = _resolve_actor(
@@ -307,7 +366,11 @@ async def refresh_meta_branches(config: Config, gitea: Gitea) -> None:
     structurally `edit/<slug>/<auto-name>` per §9.5, with dashes in place
     of slashes per the §19.2 path-routing candidate.
     """
-    org, repo = config.gitea_org, config.meta_repo
+    org = config.gitea_org
+    repo = projects_mod.default_content_repo(config)
+    if not repo:
+        log.warning("refresh_meta_branches: default project has no content_repo yet; skipping")
+        return
     try:
         branches = await gitea.list_branches(org, repo)
     except GiteaError as e:
@@ -329,16 +392,20 @@ async def refresh_meta_branches(config: Config, gitea: Gitea) -> None:
         if not slug:
             continue
         rfc = db.conn().execute(
-            "SELECT state FROM cached_rfcs WHERE slug = ?", (slug,)
+            "SELECT state, repo FROM cached_rfcs WHERE slug = ?", (slug,)
         ).fetchone()
-        if not rfc or rfc["state"] != "super-draft":
+        # Meta-only topology (§1): edit branches live on the meta repo for
+        # every meta-resident entry — super-drafts and active RFCs alike
+        # (active RFCs are graduated in place and keep editing here, §13).
+        # A legacy per-RFC repo (repo set) is the only thing excluded.
+        if not rfc or rfc["repo"] or rfc["state"] not in ("super-draft", "active"):
             continue
         edit_keys_seen.add((slug, name))
         db.conn().execute(
             """
             INSERT INTO cached_branches (rfc_slug, branch_name, head_sha, state, last_commit_at)
             VALUES (?, ?, ?, 'open', ?)
-            ON CONFLICT(rfc_slug, branch_name) DO UPDATE SET
+            ON CONFLICT(collection_id, rfc_slug, branch_name) DO UPDATE SET
                 head_sha = excluded.head_sha,
                 state = CASE WHEN cached_branches.state = 'closed' THEN 'closed' ELSE 'open' END,
                 last_commit_at = excluded.last_commit_at
@@ -352,14 +419,15 @@ async def refresh_meta_branches(config: Config, gitea: Gitea) -> None:
     # diverges from this single point.
     if meta_main_sha:
         super_drafts = db.conn().execute(
-            "SELECT slug FROM cached_rfcs WHERE state = 'super-draft'"
+            "SELECT slug FROM cached_rfcs "
+            "WHERE repo IS NULL AND state IN ('super-draft', 'active')"
         ).fetchall()
         for r in super_drafts:
             db.conn().execute(
                 """
                 INSERT INTO cached_branches (rfc_slug, branch_name, head_sha, state, last_commit_at)
                 VALUES (?, 'main', ?, 'open', ?)
-                ON CONFLICT(rfc_slug, branch_name) DO UPDATE SET
+                ON CONFLICT(collection_id, rfc_slug, branch_name) DO UPDATE SET
                     head_sha = excluded.head_sha,
                     last_commit_at = excluded.last_commit_at
                 """,
@@ -374,7 +442,8 @@ async def refresh_meta_branches(config: Config, gitea: Gitea) -> None:
         SELECT b.rfc_slug, b.branch_name
           FROM cached_branches b
           JOIN cached_rfcs r ON r.slug = b.rfc_slug
-         WHERE r.state = 'super-draft'
+         WHERE r.repo IS NULL
+           AND r.state IN ('super-draft', 'active')
            AND b.state != 'deleted'
            AND b.branch_name != 'main'
         """
@@ -418,19 +487,50 @@ async def refresh_meta_pulls(config: Config, gitea: Gitea) -> None:
     `On-behalf-of:` trailer from the PR body, then to the raw Gitea
     login as last resort.
     """
-    org, repo = config.gitea_org, config.meta_repo
+    org = config.gitea_org
+    bot_login = config.gitea_bot_user
+    rows = db.conn().execute(
+        "SELECT id, content_repo FROM projects WHERE content_repo IS NOT NULL AND content_repo != ''"
+    ).fetchall()
+    if not rows:
+        log.warning("refresh_meta_pulls: no projects with a content_repo yet; skipping")
+        return
+    for prow in rows:
+        await _refresh_project_pulls(org, prow["id"], prow["content_repo"], gitea, bot_login)
+
+
+async def _refresh_project_pulls(
+    org: str, project_id: str, repo: str, gitea: Gitea, bot_login: str
+) -> None:
     repo_full = f"{org}/{repo}"
     try:
         open_pulls = await gitea.list_pulls(org, repo, state="open")
         closed_pulls = await gitea.list_pulls(org, repo, state="closed")
     except GiteaError as e:
-        log.warning("refresh_meta_pulls: %s", e)
+        log.warning("refresh_meta_pulls: project %s: %s", project_id, e)
         return
 
-    bot_login = config.gitea_bot_user
-
     for pull in open_pulls + closed_pulls:
         head_branch = pull.get("head", {}).get("ref", "")
+        # A merged-and-deleted PR's branch is no longer reported by Gitea
+        # as its real name — the `head.ref` collapses to the synthetic
+        # `refs/pull/<N>/head` sentinel (or empty). The slug + kind both
+        # derive from the branch name, so a deleted branch would parse to
+        # slug=None and the row would be skipped forever, freezing the
+        # cached_prs row at its last-seen `state='open'` — a permanent
+        # ghost "pending idea" for an entry that has actually merged
+        # (caught when the operator authoring lane in ROADMAP #35 merged
+        # an idea PR with the branch deleted; the web UX leaves branches
+        # in place so it never tripped this). Recover the original branch
+        # from the row we already stored when the PR was open — that row
+        # retains the real `head_branch` (migration 002).
+        if not head_branch or head_branch.startswith("refs/pull/"):
+            prior = db.conn().execute(
+                "SELECT head_branch FROM cached_prs WHERE repo = ? AND pr_number = ?",
+                (repo_full, pull["number"]),
+            ).fetchone()
+            if prior and prior["head_branch"]:
+                head_branch = prior["head_branch"]
         slug = _slug_from_head_branch(head_branch)
         if slug is None:
             continue
@@ -464,8 +564,8 @@ async def refresh_meta_pulls(config: Config, gitea: Gitea) -> None:
             INSERT INTO cached_prs
                 (rfc_slug, pr_kind, repo, pr_number, title, description, state,
                  opened_by, opened_at, merged_at, closed_at,
-                 head_branch, base_branch, head_sha, merge_commit_sha)
-            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+                 head_branch, base_branch, head_sha, merge_commit_sha, project_id)
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
             ON CONFLICT(repo, pr_number) DO UPDATE SET
                 title = excluded.title,
                 description = excluded.description,
@@ -492,6 +592,7 @@ async def refresh_meta_pulls(config: Config, gitea: Gitea) -> None:
                 (pull.get("base") or {}).get("ref") or "main",
                 (pull.get("head") or {}).get("sha"),
                 merge_commit_sha,
+                project_id,
             ),
         )
 
@@ -625,6 +726,10 @@ class Reconciler:
     async def sweep(self) -> None:
         log.info("reconciler: starting sweep")
         try:
+            try:
+                await registry_mod.refresh_registry(self._config, self._gitea)
+            except Exception:
+                log.exception("reconciler: registry refresh failed; keeping last-good projects")
             await refresh_meta_repo(self._config, self._gitea)
             await refresh_meta_branches(self._config, self._gitea)
             await refresh_meta_pulls(self._config, self._gitea)

backend/app/collections.py

@@ -0,0 +1,86 @@
+"""§22 collection grain — resolution helpers beneath the project tier.
+
+In S1 each project has exactly one collection (the default). These helpers
+recover the collection for a project and read the per-corpus fields (`type`,
+`initial_state`) that moved down from `projects` in migration 029. Project-grain
+authz (auth.py) recovers a row's project by joining `collections` on
+`collection_id`.
+"""
+from __future__ import annotations
+
+from . import db
+
+DEFAULT_COLLECTION_ID = "default"
+
+
+def default_collection_id(project_id: str) -> str:
+    """The id of a project's default (S1: sole) collection. Falls back to the
+    literal 'default' when the project has no collection row yet."""
+    row = db.conn().execute(
+        "SELECT id FROM collections WHERE project_id = ? ORDER BY created_at, id LIMIT 1",
+        (project_id,),
+    ).fetchone()
+    return row["id"] if row else DEFAULT_COLLECTION_ID
+
+
+def project_of_collection(collection_id: str) -> str | None:
+    """The project a collection belongs to, or None if unknown."""
+    row = db.conn().execute(
+        "SELECT project_id FROM collections WHERE id = ?", (collection_id,)
+    ).fetchone()
+    return row["project_id"] if row else None
+
+
+def collection_initial_state(collection_id: str) -> str:
+    """§22.4b landing state for new entries in a collection. 'super-draft'
+    default for an unknown/unset row (today's safe flow)."""
+    row = db.conn().execute(
+        "SELECT initial_state FROM collections WHERE id = ?", (collection_id,)
+    ).fetchone()
+    if row is None or not row["initial_state"]:
+        return "super-draft"
+    return row["initial_state"]
+
+
+def collection_type(collection_id: str) -> str:
+    """The collection's immutable §22.4a type. 'document' default for unknown."""
+    row = db.conn().execute(
+        "SELECT type FROM collections WHERE id = ?", (collection_id,)
+    ).fetchone()
+    return row["type"] if row and row["type"] else "document"
+
+
+def subfolder_of(collection_id: str) -> str:
+    """The content-repo subfolder a collection lives under (§22.3). Empty string
+    for the default collection (entries at the repo root `rfcs/`)."""
+    row = db.conn().execute(
+        "SELECT subfolder FROM collections WHERE id = ?", (collection_id,)
+    ).fetchone()
+    return (row["subfolder"] if row else "") or ""
+
+
+def get_collection(collection_id: str) -> dict | None:
+    """The full collection row as a dict, or None if unknown."""
+    row = db.conn().execute(
+        "SELECT id, project_id, type, subfolder, initial_state, visibility, name "
+        "FROM collections WHERE id = ?",
+        (collection_id,),
+    ).fetchone()
+    return dict(row) if row else None
+
+
+def list_collections(project_id: str, include_unlisted: bool = False) -> list[dict]:
+    """Collections in a project, the default first then by name (§22.5). `unlisted`
+    is omitted from enumeration unless include_unlisted (a direct-id read or the
+    corpus mirror, which serves every collection)."""
+    rows = db.conn().execute(
+        "SELECT id, project_id, type, subfolder, initial_state, visibility, name "
+        "FROM collections WHERE project_id = ? ORDER BY (id != 'default'), name, id",
+        (project_id,),
+    ).fetchall()
+    out: list[dict] = []
+    for r in rows:
+        if not include_unlisted and r["visibility"] == "unlisted":
+            continue
+        out.append(dict(r))
+    return out

backend/app/config.py

@@ -32,7 +32,7 @@ class Config:
     gitea_bot_user: str
     gitea_bot_token: str
     gitea_org: str
-    meta_repo: str
+    registry_repo: str
     oauth_client_id: str
     oauth_client_secret: str
     app_url: str
@@ -44,14 +44,15 @@ class Config:
     anthropic_api_key: str = ""
     google_api_key: str = ""
     openai_api_key: str = ""
+    default_project_id: str = ""
 
     @property
     def redirect_uri(self) -> str:
         return f"{self.app_url}/auth/callback"
 
     @property
-    def meta_repo_full(self) -> str:
-        return f"{self.gitea_org}/{self.meta_repo}"
+    def registry_repo_full(self) -> str:
+        return f"{self.gitea_org}/{self.registry_repo}"
 
 
 def load_config() -> Config:
@@ -60,21 +61,36 @@ def load_config() -> Config:
 
     enabled = [m.strip() for m in _optional("ENABLED_MODELS", "claude").split(",") if m.strip()]
 
+    # v0.18.0: `GITEA_WEBHOOK_SECRET` is now mandatory (per the
+    # email + webhook hygiene proposal). An empty value used to
+    # silently accept unsigned webhook POSTs — that was the
+    # invisible-failure shape the proposal targets. Now the
+    # framework refuses to start when the secret is empty unless
+    # the operator opts into the dev-bypass with
+    # `RFC_APP_INSECURE_WEBHOOKS=1`. Local-dev deployments without
+    # a wired Gitea hook set the bypass; production MUST NOT.
+    insecure_webhooks = os.environ.get("RFC_APP_INSECURE_WEBHOOKS", "").strip() == "1"
+    if insecure_webhooks:
+        webhook_secret = _optional("GITEA_WEBHOOK_SECRET")
+    else:
+        webhook_secret = _required("GITEA_WEBHOOK_SECRET")
+
     return Config(
         gitea_url=_required("GITEA_URL").rstrip("/"),
         gitea_bot_user=_required("GITEA_BOT_USER"),
         gitea_bot_token=_required("GITEA_BOT_TOKEN"),
         gitea_org=_required("GITEA_ORG"),
-        meta_repo=_optional("META_REPO", "meta"),
+        registry_repo=_required("REGISTRY_REPO"),
         oauth_client_id=_required("OAUTH_CLIENT_ID"),
         oauth_client_secret=_required("OAUTH_CLIENT_SECRET"),
         app_url=_optional("APP_URL", "http://localhost:8000").rstrip("/"),
         secret_key=_required("SECRET_KEY"),
         database_path=database_path,
         owner_gitea_login=_optional("OWNER_GITEA_LOGIN"),
-        webhook_secret=_optional("GITEA_WEBHOOK_SECRET"),
+        webhook_secret=webhook_secret,
         enabled_models=enabled,
         anthropic_api_key=_optional("ANTHROPIC_API_KEY"),
         google_api_key=_optional("GOOGLE_API_KEY"),
         openai_api_key=_optional("OPENAI_API_KEY"),
+        default_project_id=_optional("DEFAULT_PROJECT_ID"),
     )

backend/app/db.py

@@ -48,7 +48,29 @@ def run_migrations(config: Config) -> None:
             if version in applied:
                 continue
             sql = path.read_text()
-            conn.executescript("BEGIN; " + sql + "; COMMIT;")
+            if "-- migrate:no-foreign-keys" in sql:
+                # SQLite table rebuilds (changing a PRIMARY KEY / UNIQUE, e.g.
+                # folding project_id into a composite key) follow the official
+                # 12-step ALTER procedure, which requires FK enforcement OFF —
+                # and `PRAGMA foreign_keys` is a no-op *inside* a transaction, so
+                # it must be toggled here, around the script. The connection is
+                # in autocommit mode (isolation_level=None), so the PRAGMA takes
+                # effect immediately. We re-enable and run foreign_key_check
+                # after, failing the migration loudly if the rebuild left any
+                # dangling reference.
+                conn.execute("PRAGMA foreign_keys = OFF")
+                try:
+                    conn.executescript("BEGIN; " + sql + "; COMMIT;")
+                    violations = conn.execute("PRAGMA foreign_key_check").fetchall()
+                    if violations:
+                        raise RuntimeError(
+                            f"migration {version} left foreign-key violations: "
+                            f"{[tuple(v) for v in violations]}"
+                        )
+                finally:
+                    conn.execute("PRAGMA foreign_keys = ON")
+            else:
+                conn.executescript("BEGIN; " + sql + "; COMMIT;")
             conn.execute("INSERT INTO schema_migrations (version) VALUES (?)", (version,))
     finally:
         conn.close()

backend/app/device_trust.py

@@ -0,0 +1,362 @@
+"""§6.2 / v0.11.0: trust device for 30 days (roadmap item #9).
+
+After a successful OTC or passcode sign-in, a contributor may check
+"trust this device for 30 days." The framework then issues a
+server-issued opaque token, hashes it (bcrypt) for storage in the
+`device_trust` table, and sets a long-lived cookie carrying the raw
+token. On a subsequent visit, the cookie is presented at
+`/auth/device-trust/start`; if a non-expired, non-revoked row matches,
+the session is re-established without another OTC / passcode round
+trip.
+
+The shape:
+
+  * `issue(user_id, user_agent)` — mint a fresh CSPRNG token, hash it,
+    insert a row, and return the raw token + row id so the endpoint
+    can set the cookie. The 30-day expiry is the only knob; the
+    `revoked_at` column stays NULL.
+  * `lookup(raw_token)` — walk the user's active rows (the unique
+    index keys on the hash, so we read a small candidate set), check
+    the bcrypt hash in constant time, drop any row whose `expires_at`
+    has passed or whose `revoked_at` is non-NULL, and return the
+    matched row or None. On a hit, refresh `last_seen_at`.
+  * `list_for_user(user_id)` — return the active rows for the
+    /settings/devices surface. Revoked + expired rows are filtered out
+    so the surface only shows live trust grants.
+  * `revoke(user_id, row_id)` — stamp `revoked_at` on the row. The
+    next lookup refuses the cookie token (the row is dead).
+  * `revoke_all(user_id)` — bulk-revoke every active row for the user.
+    The /settings/devices surface's "revoke all" button calls this.
+
+Cookie shape: `rfc_device_trust`. HttpOnly, Secure, SameSite=Lax,
+Max-Age=2592000 (30 days), Path=/. The cookie value is the raw token;
+server-side storage is the hash. The cookie is "essential" per the
+v0.13.0 cookie-consent banner (it is part of authentication, not
+analytics), so the framework sets it regardless of analytics /
+other-cookies choices.
+
+Constant-time comparison: bcrypt's `checkpw` is already constant-time
+over the hash bytes. We walk the candidate set linearly with `_check`
+which delegates to `bcrypt.checkpw`; no early-exit shortcut leaks
+which row was the match.
+
+The raw token never appears in a log line or an exception message;
+the helpers carry the token only as a parameter and forget it after
+hashing.
+
+The cookie sits orthogonal to the §6.1 `permission_state` gate: a
+revoked or pending user with a valid device-trust cookie still
+re-establishes their session (the cookie identifies the user, not
+their admission state), and the existing `require_contributor` /
+`require_admin` dependencies in `auth.py` continue to refuse the
+unrelated write surfaces.
+"""
+from __future__ import annotations
+
+import logging
+import secrets
+from dataclasses import dataclass
+
+import bcrypt
+
+from . import db
+from .auth import SessionUser
+
+log = logging.getLogger(__name__)
+
+
+# ---------------------------------------------------------------------------
+# Tunables — hard-coded in v0.11.0 (§19.2 candidate to env-ify later).
+# ---------------------------------------------------------------------------
+
+TRUST_DURATION_DAYS = 30
+COOKIE_NAME = "rfc_device_trust"
+COOKIE_MAX_AGE_SECONDS = TRUST_DURATION_DAYS * 24 * 60 * 60
+# 256 bits of CSPRNG entropy. `secrets.token_urlsafe(32)` yields ~43
+# URL-safe characters; the bcrypt hash is what's stored, so the raw
+# token only ever lives in the cookie.
+TOKEN_BYTES = 32
+# User-Agent header values seen in the wild can be unbounded; clamp
+# to a reasonable ceiling so a hostile UA doesn't bloat the row.
+USER_AGENT_MAX_LENGTH = 1024
+
+
+# ---------------------------------------------------------------------------
+# Issue
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class IssueOutcome:
+    """The shape returned from `issue`.
+
+    `raw_token` is the cookie value to send to the client; it never
+    appears in storage. `row_id` is the surrogate key for the
+    /settings/devices UI to address the row by id.
+    """
+    raw_token: str
+    row_id: int
+
+    @property
+    def cookie_value(self) -> str:
+        """The value to put in the `rfc_device_trust` cookie: the row-id
+        selector joined to the raw token (v0.25.0 / audit 0026 M1). The
+        selector lets `lookup` read one indexed row instead of scanning."""
+        return f"{self.row_id}.{self.raw_token}"
+
+
+def _new_token() -> str:
+    return secrets.token_urlsafe(TOKEN_BYTES)
+
+
+def _hash(token: str) -> str:
+    return bcrypt.hashpw(token.encode("utf-8"), bcrypt.gensalt()).decode("ascii")
+
+
+def _check(token: str, token_hash: str) -> bool:
+    try:
+        return bcrypt.checkpw(token.encode("utf-8"), token_hash.encode("ascii"))
+    except (ValueError, TypeError):
+        return False
+
+
+def _trim_user_agent(ua: str) -> str:
+    ua = (ua or "").strip()
+    if len(ua) > USER_AGENT_MAX_LENGTH:
+        return ua[:USER_AGENT_MAX_LENGTH]
+    return ua
+
+
+def issue(user_id: int, user_agent: str) -> IssueOutcome:
+    """Mint a fresh device-trust token + row for `user_id`.
+
+    The row's expiry is set 30 days in the future. The hash, not the
+    raw token, lands in the database. The caller (the endpoint) sets
+    the cookie with the raw token returned here.
+    """
+    raw = _new_token()
+    h = _hash(raw)
+    ua = _trim_user_agent(user_agent)
+    cur = db.conn().execute(
+        f"""
+        INSERT INTO device_trust (user_id, device_token_hash, expires_at, user_agent)
+        VALUES (?, ?, datetime('now', '+{TRUST_DURATION_DAYS} days'), ?)
+        """,
+        (user_id, h, ua),
+    )
+    row_id = cur.lastrowid
+    return IssueOutcome(raw_token=raw, row_id=row_id)
+
+
+# ---------------------------------------------------------------------------
+# Lookup
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class LookupOutcome:
+    """The result of `lookup`.
+
+    `user` is populated only on a hit. `reason` distinguishes the
+    failure modes so the endpoint can decide whether to clear the
+    cookie ('expired', 'revoked', 'unknown') or just refuse ('invalid').
+    """
+    ok: bool
+    user: SessionUser | None
+    reason: str  # 'ok' | 'invalid' | 'unknown' | 'expired' | 'revoked'
+    row_id: int | None = None
+
+
+def lookup(raw_token: str) -> LookupOutcome:
+    """Resolve a presented cookie token to a user.
+
+    A hit refreshes `last_seen_at` on the matched row. A miss returns
+    a reason so the endpoint can clear the stale cookie if the row
+    was revoked or expired (vs. simply unknown, which probably means
+    the cookie was forged or the row was wiped by a /settings/devices
+    revoke from another browser).
+    """
+    raw = (raw_token or "").strip()
+    if not raw:
+        return LookupOutcome(ok=False, user=None, reason="invalid")
+
+    # v0.25.0 (audit 0026 M1): the cookie is "<row_id>.<raw_token>". We
+    # parse the row-id selector and read exactly ONE row by its indexed
+    # primary key, then bcrypt-check the token against that single row.
+    #
+    # The previous shape read EVERY device_trust row (all users, including
+    # revoked/expired) and bcrypt-checked each — an unauthenticated
+    # CPU-amplification DoS reachable at /auth/device-trust/start that
+    # grew without bound as the table accumulated. bcrypt's per-row salt
+    # is why we can't SELECT by hash; carrying the row-id in the cookie is
+    # the standard fix (the id is not secret; the token still is).
+    selector, sep, token = raw.partition(".")
+    if not sep or not selector.isdigit() or not token:
+        # Legacy bare-token cookies (pre-v0.25.0) and malformed values land
+        # here. We refuse rather than fall back to a full-table scan, so
+        # the amplification path is fully closed; affected users simply
+        # re-authenticate once via OTC/passcode and get a new cookie.
+        return LookupOutcome(ok=False, user=None, reason="invalid")
+
+    matched = db.conn().execute(
+        """
+        SELECT id, user_id, device_token_hash, expires_at, revoked_at
+          FROM device_trust
+         WHERE id = ?
+        """,
+        (int(selector),),
+    ).fetchone()
+
+    # One bcrypt check, against the selected row only. A wrong/forged token
+    # for a real id reads as 'unknown' (cookie cleared), same as a missing
+    # row — a probing client can't distinguish the two.
+    if matched is None or not _check(token, matched["device_token_hash"]):
+        return LookupOutcome(ok=False, user=None, reason="unknown")
+
+    if matched["revoked_at"] is not None:
+        return LookupOutcome(ok=False, user=None, reason="revoked", row_id=matched["id"])
+
+    expired = db.conn().execute(
+        "SELECT datetime(?) < datetime('now') AS expired",
+        (matched["expires_at"],),
+    ).fetchone()["expired"]
+    if expired:
+        return LookupOutcome(ok=False, user=None, reason="expired", row_id=matched["id"])
+
+    # Refresh last-seen so the /settings/devices surface can show the
+    # user when each device was last active. This is the only write
+    # the lookup path does on the hot read.
+    db.conn().execute(
+        "UPDATE device_trust SET last_seen_at = datetime('now') WHERE id = ?",
+        (matched["id"],),
+    )
+    user_row = db.conn().execute(
+        """
+        SELECT id, gitea_id, gitea_login, email, display_name, avatar_url, role, permission_state
+          FROM users
+         WHERE id = ?
+        """,
+        (matched["user_id"],),
+    ).fetchone()
+    if user_row is None:
+        # The user row was deleted but the device_trust row hadn't
+        # cascaded yet (shouldn't happen under the FK ON DELETE
+        # CASCADE — be defensive anyway). Treat as 'unknown' so the
+        # endpoint clears the cookie.
+        return LookupOutcome(ok=False, user=None, reason="unknown", row_id=matched["id"])
+
+    # Also stamp last_seen_at on the user row so the user's overall
+    # activity stamp keeps pace with cookie-only sign-ins.
+    db.conn().execute(
+        "UPDATE users SET last_seen_at = datetime('now') WHERE id = ?",
+        (matched["user_id"],),
+    )
+
+    return LookupOutcome(
+        ok=True,
+        user=SessionUser(
+            user_id=user_row["id"],
+            gitea_id=user_row["gitea_id"] or 0,
+            gitea_login=user_row["gitea_login"] or "",
+            display_name=user_row["display_name"],
+            email=user_row["email"] or "",
+            avatar_url=user_row["avatar_url"] or "",
+            role=user_row["role"],
+            permission_state=user_row["permission_state"] or "granted",
+        ),
+        reason="ok",
+        row_id=matched["id"],
+    )
+
+
+# ---------------------------------------------------------------------------
+# List / revoke (for the /settings/devices surface)
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class DeviceRow:
+    """The shape the /settings/devices endpoint returns.
+
+    Note the absence of `device_token_hash` — the hash is structurally
+    private, and the surface has no use for it.
+    """
+    id: int
+    created_at: str
+    expires_at: str
+    last_seen_at: str
+    user_agent: str
+
+
+def list_for_user(user_id: int) -> list[DeviceRow]:
+    """Active device-trust rows for the user, freshest first.
+
+    Filters out revoked rows and rows whose expiry has passed; the
+    surface only shows live trust grants. A user wondering "which
+    devices are signed in" gets the answer that matches what the
+    framework would actually accept on a presented cookie.
+    """
+    rows = db.conn().execute(
+        """
+        SELECT id, created_at, expires_at, last_seen_at, user_agent
+          FROM device_trust
+         WHERE user_id = ?
+           AND revoked_at IS NULL
+           AND datetime(expires_at) > datetime('now')
+         ORDER BY last_seen_at DESC, id DESC
+        """,
+        (user_id,),
+    ).fetchall()
+    return [
+        DeviceRow(
+            id=row["id"],
+            created_at=row["created_at"],
+            expires_at=row["expires_at"],
+            last_seen_at=row["last_seen_at"],
+            user_agent=row["user_agent"] or "",
+        )
+        for row in rows
+    ]
+
+
+def revoke(user_id: int, row_id: int) -> bool:
+    """Revoke a single device-trust row for the given user.
+
+    Returns True iff a row was matched (still active, belongs to the
+    user). The user-id scope is enforced in SQL so a hostile client
+    cannot revoke another user's row by guessing ids.
+    """
+    cur = db.conn().execute(
+        """
+        UPDATE device_trust
+           SET revoked_at = datetime('now')
+         WHERE id = ?
+           AND user_id = ?
+           AND revoked_at IS NULL
+        """,
+        (row_id, user_id),
+    )
+    return cur.rowcount > 0
+
+
+def revoke_all(user_id: int) -> int:
+    """Revoke every active device-trust row for the user. Returns the
+    count of rows touched.
+
+    The /settings/devices "revoke all" button calls this. The user's
+    current request stays authenticated via its session cookie; the
+    device-trust cookie on the current device is also revoked, but
+    the session middleware's `rfc_session` cookie keeps the request
+    flow alive until the user signs out or the session cookie
+    expires.
+    """
+    cur = db.conn().execute(
+        """
+        UPDATE device_trust
+           SET revoked_at = datetime('now')
+         WHERE user_id = ?
+           AND revoked_at IS NULL
+        """,
+        (user_id,),
+    )
+    return cur.rowcount

backend/app/digest.py

@@ -180,7 +180,19 @@ def assemble_for_user(
 
     subject = _subject(eligible, cadence)
     body = _body(eligible, cadence, cfg)
-    sent = email_mod._deliver(cfg, email, subject, body)
+    # v0.18.0: the digest is the bulk-adjacent surface par excellence
+    # (it can carry weeks of accumulated activity), so it gets the
+    # full one-click unsubscribe to the global opt-out. Per-category
+    # opt-outs are managed from the preferences page; this footer is
+    # the "stop sending me anything" escape hatch Gmail and Yahoo
+    # expect for senders at this tier.
+    unsubscribe_url = email_mod.make_unsubscribe_url(user_id, "all")
+    sent = email_mod._deliver(
+        cfg, email, subject, body,
+        unsubscribe_mailto=cfg.unsubscribe_mailto,
+        unsubscribe_url=unsubscribe_url,
+        kind="digest",
+    )
     if not sent:
         return False
     ids = [r["id"] for r, _ in eligible]

backend/app/docs_sessions.py

@@ -0,0 +1,358 @@
+"""§14 + roadmap item #30 — on-site sessions-history browser source.
+
+Sibling of `docs.py` / `philosophy.py` but with a different read shape:
+the bodies here live in the **public** `wiggleverse/ohm-session-history`
+gitea repo (transcripts of every OHM build session, published per the
+ohm-infra SESSION-PROTOCOL.md), not on disk. The framework mediates
+the gitea fetch on behalf of the browser so the rendered `/docs/sessions/*`
+surface inherits the same chrome as `/philosophy` and `/docs/user-guide`
+and stays free of any cross-origin gestures from the frontend.
+
+Three read endpoints, all anonymous-reachable:
+
+  GET /api/docs/sessions/manifest       — sessions.json (title manifest)
+  GET /api/docs/sessions/about          — README.md (the about page)
+  GET /api/docs/sessions/<NNNN>/<file>  — a transcript body
+  GET /api/docs/sessions/<NNNN>/index   — per-session file listing
+
+All three sit behind a small in-process TTL cache (manifest TTL default
+60 s, content TTL default 300 s). Negative results (404 from gitea) are
+also cached at the content TTL to avoid hammering gitea when a
+deployment hasn't yet been populated with transcripts. The cache key
+is the URL path on the gitea raw base (or the contents API for the
+per-session listing); the cache lives in-process, plain dict +
+`time.monotonic()` check, no external dep.
+
+Env knobs:
+
+  OHM_SESSION_HISTORY_RAW_BASE
+    Override the gitea raw base URL. Default points at OHM's canonical
+    transcript repo:
+      https://git.wiggleverse.org/wiggleverse/ohm-session-history/raw/branch/main
+    The framework-default value is OHM-flavored because OHM is the
+    only deployment to date — a deployment running its own
+    transcript repo overrides this via flotilla's overlay.
+
+  OHM_SESSION_HISTORY_CONTENTS_BASE
+    Override the gitea contents-API base URL (for the per-session
+    listing endpoint, which enumerates files inside a `NNNN/` folder).
+    Default:
+      https://git.wiggleverse.org/api/v1/repos/wiggleverse/ohm-session-history/contents
+
+  OHM_DOCS_SESSIONS_MANIFEST_TTL_SEC
+    Cache TTL for the manifest (default 60 s). The manifest is small
+    and changes when a new session is added; 60 s strikes a balance
+    between freshness and gitea load.
+
+  OHM_DOCS_SESSIONS_CONTENT_TTL_SEC
+    Cache TTL for transcript bodies + README + per-session listings
+    (default 300 s = 5 minutes). Transcripts are append-only once
+    published, so 5 minutes of staleness is harmless.
+
+§3 invariant 1 is preserved: the framework holds no secret bytes; the
+gitea repo is public, the fetch carries no auth header.
+"""
+from __future__ import annotations
+
+import logging
+import os
+import re
+import threading
+import time
+from typing import Any
+
+import httpx
+
+log = logging.getLogger(__name__)
+
+
+_DEFAULT_RAW_BASE = (
+    "https://git.wiggleverse.org/wiggleverse/ohm-session-history/raw/branch/main"
+)
+_DEFAULT_CONTENTS_BASE = (
+    "https://git.wiggleverse.org/api/v1/repos/wiggleverse/ohm-session-history/contents"
+)
+_DEFAULT_MANIFEST_TTL_SEC = 60.0
+_DEFAULT_CONTENT_TTL_SEC = 300.0
+
+# The transcript filename shape per SESSION-PROTOCOL.md §1. The
+# `<start>--<end>` suffix is optional so legacy renamed-letter
+# transcripts (e.g. `SESSION-0009.0-TRANSCRIPT.md` without timestamps)
+# remain reachable. The `\.\d+(\.\d+)*` after the session number
+# accommodates `0017.0`, `0017.1`, `0017.1.1`, etc.
+_TRANSCRIPT_FILENAME_RE = re.compile(
+    r"^SESSION-\d{4}\.\d+(\.\d+)*-TRANSCRIPT"
+    r"(-\d{4}-\d{2}-\d{2}T\d{2}-\d{2}--\d{4}-\d{2}-\d{2}T\d{2}-\d{2})?"
+    r"\.md$"
+)
+_SESSION_DIR_RE = re.compile(r"^\d{4}$")
+
+_HTTP_TIMEOUT_SEC = 5.0
+
+
+def _env_float(name: str, default: float) -> float:
+    raw = os.environ.get(name, "").strip()
+    if not raw:
+        return default
+    try:
+        return float(raw)
+    except ValueError:
+        log.warning("invalid %s=%r — falling back to %s", name, raw, default)
+        return default
+
+
+def _raw_base() -> str:
+    return os.environ.get("OHM_SESSION_HISTORY_RAW_BASE", "").strip() or _DEFAULT_RAW_BASE
+
+
+def _contents_base() -> str:
+    return (
+        os.environ.get("OHM_SESSION_HISTORY_CONTENTS_BASE", "").strip()
+        or _DEFAULT_CONTENTS_BASE
+    )
+
+
+def _manifest_ttl() -> float:
+    return _env_float("OHM_DOCS_SESSIONS_MANIFEST_TTL_SEC", _DEFAULT_MANIFEST_TTL_SEC)
+
+
+def _content_ttl() -> float:
+    return _env_float("OHM_DOCS_SESSIONS_CONTENT_TTL_SEC", _DEFAULT_CONTENT_TTL_SEC)
+
+
+# ---------------------------------------------------------------------------
+# In-process TTL cache
+# ---------------------------------------------------------------------------
+#
+# Plain dict + `time.monotonic()` check, no external dep. The cache
+# value is a `(stored_at, payload)` tuple; `payload` may carry an
+# error-shape sentinel for negative caching (404s). Lock guards
+# read-modify-write across worker tasks; entries are immutable once
+# stored so reads under the lock are fast.
+
+_lock = threading.Lock()
+_cache: dict[str, tuple[float, dict[str, Any]]] = {}
+
+
+def _cache_get(key: str, ttl_sec: float) -> dict[str, Any] | None:
+    with _lock:
+        entry = _cache.get(key)
+        if entry is None:
+            return None
+        stored_at, payload = entry
+        if time.monotonic() - stored_at > ttl_sec:
+            # Don't evict here; let _cache_put overwrite on next fetch.
+            # The stale entry is gated by the TTL check, so it stays
+            # invisible to readers regardless.
+            return None
+        return payload
+
+
+def _cache_put(key: str, payload: dict[str, Any]) -> None:
+    with _lock:
+        _cache[key] = (time.monotonic(), payload)
+
+
+def reset_cache() -> None:
+    """Drop every cached entry. Test seam — not called in production."""
+    with _lock:
+        _cache.clear()
+
+
+# ---------------------------------------------------------------------------
+# Public fetch surface
+# ---------------------------------------------------------------------------
+#
+# Each fetcher returns a `{status, ...}` dict. `status` is one of:
+#   "ok"     — payload field carries the body
+#   "404"    — gitea returned 404 (or content was missing)
+#   "error"  — gitea returned 5xx, timed out, or returned malformed data
+#
+# The route layer maps these onto HTTP responses; keeping the mapping
+# out of this module makes the cache transparent to the test harness.
+
+
+async def _http_get(url: str) -> tuple[int, str]:
+    """Perform a single GET against `url`; return (status_code, body).
+
+    On timeout or network error, returns (599, error_message). The 599
+    pseudo-status maps to a 502 at the route layer the same way an
+    upstream 5xx does — the caller doesn't care which leg of the
+    network broke.
+    """
+    try:
+        async with httpx.AsyncClient(timeout=_HTTP_TIMEOUT_SEC) as client:
+            r = await client.get(url)
+            return r.status_code, r.text
+    except httpx.HTTPError as e:
+        log.warning("gitea fetch failed for %s: %s", url, e)
+        return 599, f"fetch error: {e}"
+
+
+def _is_valid_session_dir(nnnn: str) -> bool:
+    return bool(_SESSION_DIR_RE.match(nnnn))
+
+
+def _is_valid_transcript_filename(filename: str) -> bool:
+    return bool(_TRANSCRIPT_FILENAME_RE.match(filename))
+
+
+async def fetch_manifest() -> dict[str, Any]:
+    """Fetch and parse `sessions.json` from the public repo.
+
+    Returns one of:
+      {"status": "ok", "manifest": {...}}        — successful parse
+      {"status": "404"}                          — gitea 404 (empty state)
+      {"status": "error", "detail": "..."}       — 5xx / timeout / bad JSON
+    """
+    cache_key = "manifest"
+    cached = _cache_get(cache_key, _manifest_ttl())
+    if cached is not None:
+        return cached
+
+    url = f"{_raw_base()}/sessions.json"
+    status, body = await _http_get(url)
+
+    if status == 200:
+        try:
+            import json
+
+            data = json.loads(body)
+        except (json.JSONDecodeError, ValueError) as e:
+            payload: dict[str, Any] = {
+                "status": "error",
+                "detail": f"sessions.json malformed: {e}",
+            }
+            # Don't cache parse errors — give the upstream a chance to
+            # fix the file without waiting for TTL expiry.
+            return payload
+        if not isinstance(data, dict):
+            return {
+                "status": "error",
+                "detail": "sessions.json is not a JSON object",
+            }
+        payload = {"status": "ok", "manifest": data}
+        _cache_put(cache_key, payload)
+        return payload
+
+    if status == 404:
+        payload = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+
+    return {"status": "error", "detail": f"upstream returned {status}"}
+
+
+async def fetch_about() -> dict[str, Any]:
+    """Fetch the repo's README.md (rendered as the /docs/sessions/about page).
+
+    Returns one of:
+      {"status": "ok", "body": "..."}
+      {"status": "404"}
+      {"status": "error", "detail": "..."}
+    """
+    cache_key = "about:README.md"
+    cached = _cache_get(cache_key, _content_ttl())
+    if cached is not None:
+        return cached
+
+    url = f"{_raw_base()}/README.md"
+    status, body = await _http_get(url)
+
+    if status == 200:
+        payload: dict[str, Any] = {"status": "ok", "body": body}
+        _cache_put(cache_key, payload)
+        return payload
+    if status == 404:
+        payload = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+    return {"status": "error", "detail": f"upstream returned {status}"}
+
+
+async def fetch_transcript(nnnn: str, filename: str) -> dict[str, Any]:
+    """Fetch a single transcript body from `{nnnn}/{filename}` in the repo.
+
+    The caller is expected to have validated `nnnn` and `filename`
+    against `_is_valid_session_dir` / `_is_valid_transcript_filename`
+    before calling this — invalid paths shouldn't reach the network.
+    """
+    cache_key = f"transcript:{nnnn}/{filename}"
+    cached = _cache_get(cache_key, _content_ttl())
+    if cached is not None:
+        return cached
+
+    url = f"{_raw_base()}/{nnnn}/{filename}"
+    status, body = await _http_get(url)
+
+    if status == 200:
+        payload: dict[str, Any] = {"status": "ok", "body": body}
+        _cache_put(cache_key, payload)
+        return payload
+    if status == 404:
+        payload = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+    return {"status": "error", "detail": f"upstream returned {status}"}
+
+
+async def fetch_session_index(nnnn: str) -> dict[str, Any]:
+    """List the transcript filenames inside the `{nnnn}/` folder.
+
+    Uses gitea's contents API (one HTTP per session-index page-view per
+    cache-TTL) rather than the raw URL — there's no flat way to list a
+    folder via the raw mount.
+
+    Returns one of:
+      {"status": "ok", "files": ["SESSION-...md", ...]}
+      {"status": "404"}
+      {"status": "error", "detail": "..."}
+
+    Only filenames that match `_is_valid_transcript_filename` are
+    surfaced — sibling files (e.g. an attached `notes.md`) are ignored
+    so the /docs/sessions/<NNNN> page never lists a non-transcript
+    masquerading as one.
+    """
+    cache_key = f"index:{nnnn}"
+    cached = _cache_get(cache_key, _content_ttl())
+    if cached is not None:
+        return cached
+
+    url = f"{_contents_base()}/{nnnn}"
+    status, body = await _http_get(url)
+
+    if status == 200:
+        try:
+            import json
+
+            data = json.loads(body)
+        except (json.JSONDecodeError, ValueError) as e:
+            return {
+                "status": "error",
+                "detail": f"contents API response malformed: {e}",
+            }
+        if not isinstance(data, list):
+            return {
+                "status": "error",
+                "detail": "contents API returned non-list",
+            }
+        files: list[str] = []
+        for entry in data:
+            if not isinstance(entry, dict):
+                continue
+            if entry.get("type") != "file":
+                continue
+            name = entry.get("name")
+            if not isinstance(name, str):
+                continue
+            if _is_valid_transcript_filename(name):
+                files.append(name)
+        files.sort()
+        payload: dict[str, Any] = {"status": "ok", "files": files}
+        _cache_put(cache_key, payload)
+        return payload
+    if status == 404:
+        payload = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+    return {"status": "error", "detail": f"upstream returned {status}"}

backend/app/docs_specs.py

@@ -0,0 +1,326 @@
+"""v0.20.0 — on-site framework-specs surface source.
+
+Sibling of `docs_sessions.py` (v0.19.0 / roadmap item #30): the
+framework mediates a gitea fetch on behalf of the browser so the
+rendered `/docs/specs/*` surface inherits the same chrome as
+`/docs/user-guide` and `/docs/sessions/*` and stays free of any
+cross-origin gestures from the frontend.
+
+Two read endpoints, both anonymous-reachable:
+
+  GET /api/docs/specs/manifest   — the configured spec list
+  GET /api/docs/specs/<name>     — a single spec body (markdown)
+
+The framework-default manifest is OHM-flavored (rfc-app's own SPEC.md
++ flotilla's SPEC.md on `git.wiggleverse.org`) for the same reason
+`docs_sessions.py`'s defaults are: OHM is the only deployment to
+date. A deployment running its own spec set overrides the manifest
+via the `OHM_DOCS_SPECS` env var (set through flotilla's overlay).
+History is intentionally not surfaced here — the operator-stated
+intent is "current version only; git is the history surface".
+
+Per-spec entries carry three fields:
+
+  name   — URL-safe slug (`[a-z0-9-]+`) — the path segment
+  title  — human-readable label shown in the nav and the page header
+  url    — the upstream raw URL the framework fetches
+
+Validation:
+
+  - The configured list must be a JSON array of `{name, title, url}`
+    objects. A malformed `OHM_DOCS_SPECS` value (bad JSON, wrong
+    shape, invalid slug) logs a warning and falls back to the default
+    so a typo in the overlay doesn't crash startup.
+  - Each `name` is checked against `^[a-z0-9-]+$` before the manifest
+    is accepted. The route layer also validates the path-bound `name`
+    parameter before any network call, so a malformed URL never
+    reaches the cache or the upstream.
+
+Cache shape mirrors `docs_sessions.py`: in-process `dict` + monotonic
+TTL check, negative results (404) cached, no external dep. The
+manifest is cheap (parsed from an env var, no network), so it has no
+TTL — every request re-derives it. Per-spec content has a 5-minute
+default TTL (env-tunable via `OHM_DOCS_SPECS_CONTENT_TTL_SEC`).
+
+§3 invariant 1 is preserved: the framework holds no secret bytes;
+the upstream specs are public-repo raw URLs, the fetch carries no
+auth header.
+"""
+from __future__ import annotations
+
+import json
+import logging
+import os
+import re
+import threading
+import time
+from typing import Any
+
+import httpx
+
+log = logging.getLogger(__name__)
+
+
+# The framework-default spec set. OHM-flavored per the same precedent
+# `docs_sessions.py` set: the only live deployment is OHM, so the
+# default points there. A deployment running its own specs overrides
+# `OHM_DOCS_SPECS` via the overlay.
+_DEFAULT_SPECS: list[dict[str, str]] = [
+    {
+        "name": "rfc-app",
+        "title": "rfc-app SPEC",
+        "url": (
+            "https://git.wiggleverse.org/ben.stull/rfc-app/"
+            "raw/branch/main/SPEC.md"
+        ),
+    },
+    {
+        "name": "flotilla",
+        "title": "flotilla SPEC",
+        "url": (
+            "https://git.wiggleverse.org/wiggleverse/ohm-rfc-app-flotilla/"
+            "raw/branch/main/SPEC.md"
+        ),
+    },
+]
+
+_DEFAULT_CONTENT_TTL_SEC = 300.0
+
+# URL-safe slug. Matches `docs_sessions.py`'s `_SESSION_DIR_RE` spirit
+# (rejecting anything that could resolve outside the intended layout)
+# but with the lowercase-alphanumeric-plus-dash shape the manifest
+# enforces. Path traversal (`..`), separators (`/`), tilde, uppercase,
+# and whitespace all fail this regex; the route layer rejects 400
+# before any cache or network call.
+_NAME_RE = re.compile(r"^[a-z0-9-]+$")
+
+_HTTP_TIMEOUT_SEC = 5.0
+
+
+def _env_float(name: str, default: float) -> float:
+    raw = os.environ.get(name, "").strip()
+    if not raw:
+        return default
+    try:
+        return float(raw)
+    except ValueError:
+        log.warning("invalid %s=%r — falling back to %s", name, raw, default)
+        return default
+
+
+def _content_ttl() -> float:
+    return _env_float("OHM_DOCS_SPECS_CONTENT_TTL_SEC", _DEFAULT_CONTENT_TTL_SEC)
+
+
+def _is_valid_name(name: str) -> bool:
+    """Slug guard for path-bound `name` parameters.
+
+    Mirrors `docs_sessions._is_valid_session_dir`'s contract: the
+    route layer calls this before any network or cache work, so a
+    malformed name never escapes the FastAPI surface.
+    """
+    return bool(isinstance(name, str) and _NAME_RE.match(name))
+
+
+def _parse_spec_entry(entry: Any) -> dict[str, str] | None:
+    """Validate a single manifest entry; return None if invalid.
+
+    Required fields: `name`, `title`, `url`. All three must be
+    non-empty strings; `name` must match `_NAME_RE`. The validator is
+    strict: an entry that fails any check is dropped from the manifest
+    (and the caller logs at warning level).
+    """
+    if not isinstance(entry, dict):
+        return None
+    name = entry.get("name")
+    title = entry.get("title")
+    url = entry.get("url")
+    if not isinstance(name, str) or not _is_valid_name(name):
+        return None
+    if not isinstance(title, str) or not title.strip():
+        return None
+    if not isinstance(url, str) or not url.strip():
+        return None
+    return {"name": name, "title": title.strip(), "url": url.strip()}
+
+
+def _load_configured_specs() -> list[dict[str, str]]:
+    """Parse `OHM_DOCS_SPECS` (if set) or return the default list.
+
+    Malformed JSON or wrong-shape values log a warning and fall back
+    to the default — the deployment continues to render the spec
+    surface rather than crashing startup. The strict validation (each
+    entry's name slug, presence of all three fields) drops bad entries
+    one-by-one; if every entry is dropped, the default applies.
+    """
+    raw = os.environ.get("OHM_DOCS_SPECS", "").strip()
+    if not raw:
+        return list(_DEFAULT_SPECS)
+    try:
+        parsed = json.loads(raw)
+    except (json.JSONDecodeError, ValueError) as e:
+        log.warning(
+            "OHM_DOCS_SPECS is not valid JSON (%s) — falling back to default", e
+        )
+        return list(_DEFAULT_SPECS)
+    if not isinstance(parsed, list):
+        log.warning(
+            "OHM_DOCS_SPECS must be a JSON array — falling back to default"
+        )
+        return list(_DEFAULT_SPECS)
+    out: list[dict[str, str]] = []
+    seen: set[str] = set()
+    for entry in parsed:
+        validated = _parse_spec_entry(entry)
+        if validated is None:
+            log.warning(
+                "OHM_DOCS_SPECS entry %r failed validation — dropped", entry
+            )
+            continue
+        if validated["name"] in seen:
+            log.warning(
+                "OHM_DOCS_SPECS has duplicate name %r — dropped", validated["name"]
+            )
+            continue
+        seen.add(validated["name"])
+        out.append(validated)
+    if not out:
+        log.warning(
+            "OHM_DOCS_SPECS yielded no valid entries — falling back to default"
+        )
+        return list(_DEFAULT_SPECS)
+    return out
+
+
+# ---------------------------------------------------------------------------
+# In-process TTL cache
+# ---------------------------------------------------------------------------
+#
+# Same shape as `docs_sessions.py`: plain dict + `time.monotonic()` check,
+# no external dep. The cache value is a `(stored_at, payload)` tuple;
+# `payload` may carry an error-shape sentinel for negative caching (404s).
+# Lock guards read-modify-write across worker tasks; entries are immutable
+# once stored so reads under the lock are fast.
+
+_lock = threading.Lock()
+_cache: dict[str, tuple[float, dict[str, Any]]] = {}
+
+
+def _cache_get(key: str, ttl_sec: float) -> dict[str, Any] | None:
+    with _lock:
+        entry = _cache.get(key)
+        if entry is None:
+            return None
+        stored_at, payload = entry
+        if time.monotonic() - stored_at > ttl_sec:
+            return None
+        return payload
+
+
+def _cache_put(key: str, payload: dict[str, Any]) -> None:
+    with _lock:
+        _cache[key] = (time.monotonic(), payload)
+
+
+def reset_cache() -> None:
+    """Drop every cached entry. Test seam — not called in production."""
+    with _lock:
+        _cache.clear()
+
+
+# ---------------------------------------------------------------------------
+# Public fetch surface
+# ---------------------------------------------------------------------------
+#
+# Each fetcher returns a `{status, ...}` dict, same convention as
+# `docs_sessions.py`:
+#   "ok"     — payload field carries the body / manifest
+#   "404"    — gitea returned 404 (or the configured name doesn't exist)
+#   "error"  — gitea returned 5xx, timed out, or returned malformed data
+#
+# The route layer maps these onto HTTP responses; keeping the mapping
+# out of this module makes the cache transparent to the test harness.
+
+
+async def _http_get(url: str) -> tuple[int, str]:
+    """Perform a single GET against `url`; return (status_code, body).
+
+    On timeout or network error, returns (599, error_message). The 599
+    pseudo-status maps to a 502 at the route layer the same way an
+    upstream 5xx does — the caller doesn't care which leg of the
+    network broke.
+    """
+    try:
+        async with httpx.AsyncClient(timeout=_HTTP_TIMEOUT_SEC) as client:
+            r = await client.get(url)
+            return r.status_code, r.text
+    except httpx.HTTPError as e:
+        log.warning("specs fetch failed for %s: %s", url, e)
+        return 599, f"fetch error: {e}"
+
+
+def fetch_specs_manifest() -> dict[str, Any]:
+    """Return the configured spec manifest.
+
+    The manifest is derived from the `OHM_DOCS_SPECS` env var (or the
+    framework default if unset / malformed) and carries no network
+    work — it's safe to call on every request. The return shape mirrors
+    the docs_sessions manifest endpoint for frontend consistency:
+
+      {"status": "ok", "specs": [{"name", "title", "url"}, ...]}
+
+    The "url" field is exposed in the manifest so the frontend can
+    offer a "view source on gitea" affordance alongside each rendered
+    spec (operator-stated intent: "include the history so you can see
+    it in git" — that gesture lives in the source link, not on the
+    rendered page).
+    """
+    specs = _load_configured_specs()
+    return {"status": "ok", "specs": specs}
+
+
+async def fetch_spec(name: str) -> dict[str, Any]:
+    """Fetch a single spec body by its manifest `name`.
+
+    The caller is expected to have validated `name` against
+    `_is_valid_name` before calling this — an invalid name shouldn't
+    reach the network. We re-check inside as defense-in-depth: a
+    bogus name here returns the same `{status: "404"}` shape so the
+    route layer's `404 → HTTP 404` mapping handles it uniformly.
+
+    Returns one of:
+      {"status": "ok", "body": "..."}
+      {"status": "404"}                      — no such spec OR upstream 404
+      {"status": "error", "detail": "..."}   — upstream 5xx / timeout
+    """
+    if not _is_valid_name(name):
+        return {"status": "404"}
+
+    cache_key = f"spec:{name}"
+    cached = _cache_get(cache_key, _content_ttl())
+    if cached is not None:
+        return cached
+
+    specs = _load_configured_specs()
+    match = next((s for s in specs if s["name"] == name), None)
+    if match is None:
+        # Cache the negative — a deployment with an unstable manifest
+        # would still benefit from the TTL window, and the cached 404
+        # is automatically displaced when the next request happens
+        # after TTL expiry.
+        payload: dict[str, Any] = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+
+    url = match["url"]
+    status, body = await _http_get(url)
+
+    if status == 200:
+        payload = {"status": "ok", "body": body}
+        _cache_put(cache_key, payload)
+        return payload
+    if status == 404:
+        payload = {"status": "404"}
+        _cache_put(cache_key, payload)
+        return payload
+    return {"status": "error", "detail": f"upstream returned {status}"}

backend/app/email.py

@@ -24,7 +24,6 @@ import os
 import smtplib
 from dataclasses import dataclass
 from datetime import datetime, time, timezone
-from email.message import EmailMessage
 from email.utils import formataddr
 from itertools import groupby
 from typing import Any
@@ -33,6 +32,7 @@ from urllib.parse import urlencode
 from itsdangerous import BadSignature, URLSafeSerializer
 
 from . import db
+from .email_envelope import build_envelope
 
 log = logging.getLogger(__name__)
 
@@ -69,6 +69,7 @@ class EmailConfig:
     app_url: str
     bundle_threshold: int
     enabled: bool
+    unsubscribe_mailto: str
 
     @classmethod
     def from_env(cls) -> "EmailConfig":
@@ -84,6 +85,16 @@ class EmailConfig:
             app_url=os.environ.get("APP_URL", "http://localhost:8000").rstrip("/"),
             bundle_threshold=int(os.environ.get("EMAIL_BUNDLE_THRESHOLD", "5")),
             enabled=os.environ.get("EMAIL_ENABLED", "1") not in ("0", "false", "False"),
+            # v0.18.0: the `List-Unsubscribe: <mailto:…>` target on
+            # invite + notification mail. Defaults to the From
+            # address when unset; a deployment can route opt-out
+            # mail to a separate mailbox (e.g., a humans-monitored
+            # account distinct from the no-reply notifications
+            # sender) by setting this explicitly.
+            unsubscribe_mailto=os.environ.get(
+                "EMAIL_UNSUBSCRIBE_MAILTO",
+                os.environ.get("EMAIL_FROM", "notifications@wiggleverse.local"),
+            ).strip(),
         )
 
 
@@ -98,6 +109,14 @@ def _signer() -> URLSafeSerializer:
 
 
 def make_unsubscribe_url(user_id: int, category: str) -> str:
+    """Build the §15.4 per-category one-click URL.
+
+    `category` is one of `personal-direct`, `structural`,
+    `admin-actionable` (the three per-category flags) or `all`
+    (v0.18.0: the bundle path, which sets `email_opt_out_all = 1`
+    because a bundle covers multiple categories and a per-category
+    opt-out wouldn't honor the user's intent).
+    """
     cfg = EmailConfig.from_env()
     token = _signer().dumps({"u": user_id, "c": category})
     qs = urlencode({"t": token})
@@ -250,7 +269,21 @@ def _send_one(user: Any, notif_id: int, payload: dict, category: str) -> None:
         return
     subject = _subject(payload)
     body = _body(payload, user["id"], category, cfg)
-    sent = _deliver(cfg, user["email"], subject, body)
+    # v0.18.0: notification mail is bulk-adjacent (a watcher can
+    # accumulate dozens of structural events on a busy RFC), so it
+    # carries the full one-click unsubscribe — Gmail and Yahoo
+    # require this for senders at OHM's volume tier per RFC 8058.
+    unsubscribe_url = make_unsubscribe_url(user["id"], category)
+    sent = _deliver(
+        cfg,
+        user["email"],
+        subject,
+        body,
+        unsubscribe_mailto=cfg.unsubscribe_mailto,
+        unsubscribe_url=unsubscribe_url,
+        kind="notification",
+        notification_id=notif_id,
+    )
     if not sent:
         return
     db.conn().execute(
@@ -305,23 +338,65 @@ def _deep_link(payload: dict, cfg: EmailConfig) -> str:
     return cfg.app_url
 
 
-def _deliver(cfg: EmailConfig, to_address: str, subject: str, body: str) -> bool:
+def _deliver(
+    cfg: EmailConfig,
+    to_address: str,
+    subject: str,
+    body: str,
+    *,
+    unsubscribe_mailto: str | None = None,
+    unsubscribe_url: str | None = None,
+    kind: str = "notification",
+    notification_id: int | None = None,
+) -> bool:
+    """Build the envelope via the shared `build_envelope` helper and
+    hand it to SMTP.
+
+    The `_SENT` buffer carries the helper's `EmailMessage` under
+    `message` plus the legacy `to`/`from`/`subject`/`body` keys for
+    backward-compatibility with tests that read those directly.
+    Newer tests can assert on the header surface by inspecting
+    `envelope["message"]`.
+
+    v0.18.0 Slice 4: also writes one row to `outbound_emails`
+    capturing the attempt. status='sent' on success, 'failed' on
+    SMTP exception, 'deferred' on the dev-fallback path (no
+    SMTP_HOST configured — the send didn't happen, but the row
+    records the attempt so the admin endpoint can answer "did the
+    framework try?").
+    """
+    msg = build_envelope(
+        to_address=to_address,
+        from_address=cfg.from_address,
+        from_name=cfg.from_name,
+        subject=subject,
+        body_plain=body,
+        unsubscribe_mailto=unsubscribe_mailto,
+        unsubscribe_url=unsubscribe_url,
+    )
     envelope = {
         "to": to_address,
         "from": formataddr((cfg.from_name, cfg.from_address)),
         "subject": subject,
         "body": body,
+        "message": msg,
+        "kind": kind,
     }
     _SENT.append(envelope)
+    message_id = msg["Message-ID"]
     if not cfg.smtp_host:
         log.info("email (stdout fallback): to=%s subject=%s", to_address, subject)
+        record_outbound(
+            to_address=to_address,
+            from_address=cfg.from_address,
+            subject=subject,
+            kind=kind,
+            status="deferred",
+            message_id=message_id,
+            notification_id=notification_id,
+        )
         return True
     try:
-        msg = EmailMessage()
-        msg["From"] = envelope["from"]
-        msg["To"] = to_address
-        msg["Subject"] = subject
-        msg.set_content(body)
         smtp = smtplib.SMTP(cfg.smtp_host, cfg.smtp_port, timeout=30)
         try:
             if cfg.smtp_starttls:
@@ -331,12 +406,78 @@ def _deliver(cfg: EmailConfig, to_address: str, subject: str, body: str) -> bool
             smtp.send_message(msg)
         finally:
             smtp.quit()
+        record_outbound(
+            to_address=to_address,
+            from_address=cfg.from_address,
+            subject=subject,
+            kind=kind,
+            status="sent",
+            message_id=message_id,
+            notification_id=notification_id,
+        )
         return True
-    except Exception:
+    except Exception as exc:
         log.exception("email send failed: to=%s subject=%s", to_address, subject)
+        record_outbound(
+            to_address=to_address,
+            from_address=cfg.from_address,
+            subject=subject,
+            kind=kind,
+            status="failed",
+            error=f"{type(exc).__name__}: {exc}",
+            message_id=message_id,
+            notification_id=notification_id,
+        )
         return False
 
 
+def record_outbound(
+    *,
+    to_address: str,
+    from_address: str,
+    subject: str,
+    kind: str,
+    status: str,
+    error: str | None = None,
+    notification_id: int | None = None,
+    message_id: str | None = None,
+) -> int | None:
+    """v0.18.0 Slice 4: write one row to `outbound_emails`.
+
+    Returns the inserted row's id, or `None` if the DB connection
+    isn't initialized (which happens in unit tests that don't boot
+    the full app — the write is best-effort and never raises).
+    """
+    try:
+        cur = db.conn().execute(
+            """
+            INSERT INTO outbound_emails
+                (to_address, from_address, subject, kind, sent_at, status,
+                 error, notification_id, message_id)
+            VALUES (?, ?, ?, ?, datetime('now'), ?, ?, ?, ?)
+            """,
+            (
+                to_address,
+                from_address,
+                subject,
+                kind,
+                status,
+                error,
+                notification_id,
+                message_id,
+            ),
+        )
+        return cur.lastrowid
+    except RuntimeError:
+        # db.conn() raises RuntimeError if init() hasn't been called.
+        # Pure-helper unit tests for build_envelope hit this path; the
+        # audit row is best-effort and not part of the contract.
+        return None
+    except Exception:
+        log.exception("outbound_emails write failed: to=%s subject=%s", to_address, subject)
+        return None
+
+
 # ---------------------------------------------------------------------------
 # Quiet-hours release pass — called from the digest job
 # ---------------------------------------------------------------------------
@@ -440,13 +581,27 @@ def _send_bundle(cfg: EmailConfig, user: Any, emailable: list) -> int:
         for r, _cat, extras in group_rows:
             summary = _summary_for(r["event_kind"], r["actor_display"], r["rfc_title"], extras)
             sections.append(f"  · {summary}")
+    # v0.18.0: the bundle covers multiple categories, so a
+    # per-category opt-out can't honor the user's intent. The
+    # `all` category lands at the §15.4 endpoint and sets
+    # `email_opt_out_all = 1`.
+    unsubscribe_url = make_unsubscribe_url(user["id"], "all")
     body = (
         "Activity on RFCs you watch, accumulated during your quiet hours:\n"
         + "\n".join(sections)
         + f"\n\nOpen your inbox: {cfg.app_url}/inbox\n"
         + f"Manage all preferences: {cfg.app_url}/settings/notifications\n"
+        + f"Unsubscribe from all email: {unsubscribe_url}\n"
+    )
+    sent = _deliver(
+        cfg,
+        user["email"],
+        subject,
+        body,
+        unsubscribe_mailto=cfg.unsubscribe_mailto,
+        unsubscribe_url=unsubscribe_url,
+        kind="bundle",
     )
-    sent = _deliver(cfg, user["email"], subject, body)
     if not sent:
         return 0
     ids = [r["id"] for r, _, _ in emailable]

backend/app/email_envelope.py

@@ -0,0 +1,155 @@
+"""v0.18.0 / roadmap items #18 + #20: a shared envelope builder.
+
+Every outbound mail in rfc-app today (OTC, admin-invite, watcher
+notification, "while you were away" bundle, per-RFC invite) constructs
+its own `email.message.EmailMessage` ad-hoc. The four sites diverged
+just enough to be a deliverability hazard: missing `Date`, missing
+`Message-ID`, no `Auto-Submitted`, no `List-Unsubscribe` on the
+bulk-adjacent paths, no `multipart/alternative` body.
+
+This module is the one place an `EmailMessage` is constructed. Every
+send path imports `build_envelope` and calls it; the headers that
+matter for inbox placement (Date, Message-ID, Auto-Submitted) land
+uniformly, and the per-kind variations (unsubscribe semantics,
+HTML alternative) are explicit arguments rather than buried in
+each call site.
+
+Per the v0.18.0 proposal at `~/git/ohm-infra/RFC-APP-EMAIL-HYGIENE-PROPOSAL.md`,
+the per-kind unsubscribe matrix is:
+
+  * OTC: no `List-Unsubscribe` (the recipient explicitly requested
+    the code; advertising an unsubscribe header would imply OHM has
+    them on a list, which it doesn't).
+  * Admin invite / per-RFC invite: `mailto:` form only (the
+    recipient isn't a user yet, so there's no per-user opt-out row
+    to flip; the operator handles ad-hoc opt-outs manually).
+  * Watcher notification / bundle: full `mailto:` + signed-URL
+    `List-Unsubscribe` plus `List-Unsubscribe-Post:
+    List-Unsubscribe=One-Click` per RFC 8058 (Gmail and Yahoo
+    enforce this for bulk-adjacent senders).
+
+The `is_transactional` flag governs `Auto-Submitted: auto-generated`,
+which prevents auto-responder loops on every kind of mail we send.
+All five mail kinds today are transactional in the SMTP sense (no
+human is at the From mailbox watching for replies), so the default
+is True; the argument is exposed for future symmetry.
+"""
+from __future__ import annotations
+
+from email.message import EmailMessage
+from email.utils import formataddr, formatdate, make_msgid
+
+
+def build_envelope(
+    *,
+    to_address: str,
+    from_address: str,
+    from_name: str,
+    subject: str,
+    body_plain: str,
+    body_html: str | None = None,
+    reply_to: str | None = None,
+    unsubscribe_mailto: str | None = None,
+    unsubscribe_url: str | None = None,
+    is_transactional: bool = True,
+    msgid_domain: str | None = None,
+) -> EmailMessage:
+    """Compose an `EmailMessage` with hardened headers.
+
+    `to_address` / `from_address` are bare RFC 5322 addresses;
+    `from_name` is the display label that goes through `formataddr`
+    so spaces / commas in the display string are encoded correctly.
+
+    `body_plain` is mandatory. `body_html` is **reserved and not yet
+    enabled** (security-audit-0026 I3): no send path supplies it today —
+    every rfc-app mail is plain text — and passing it raises
+    `NotImplementedError`. The parameter is kept in the signature for
+    documented future symmetry: when HTML mail is enabled it will land
+    as the second part of a `multipart/alternative` body (text/plain
+    first per RFC 2046, so a plain-text client picking the first part
+    still gets the readable text). Enabling it is a deliberate act — the
+    caller MUST HTML-escape any user content into `body_html` first (cf.
+    the C1 stored-XSS class: a mail client renders the HTML) and remove
+    the guard below in the same change.
+
+    `reply_to`, when set, lets a send path point replies at a
+    different mailbox than the From line (e.g., a watcher
+    notification with From=notifications@... but Reply-To=
+    ohm@... so a confused recipient who hits Reply lands at a
+    monitored mailbox).
+
+    `unsubscribe_mailto` / `unsubscribe_url` populate
+    `List-Unsubscribe`. If `unsubscribe_url` is set, the helper also
+    emits `List-Unsubscribe-Post: List-Unsubscribe=One-Click` per
+    RFC 8058 — Gmail and Yahoo POST that payload on the user's
+    one-click action. (Send paths that wire `unsubscribe_url`
+    therefore MUST also expose a matching POST endpoint that accepts
+    the same token; see `api_notifications.py:email_unsubscribe`.)
+
+    `msgid_domain` defaults to the @-domain of `from_address` so
+    Message-IDs are aligned with the sending domain by default. A
+    deployment that wants the Message-ID domain to track a different
+    surface (e.g., a tracking-domain that's separate from the From
+    domain) can override.
+
+    `Date` is RFC 5322 formatted via `email.utils.formatdate`; the
+    `localtime=True` setting picks the running process's local
+    timezone, which is what every popular MUA does too. (A
+    deployment running in UTC stamps UTC; that's correct, not a
+    bug.)
+    """
+    msg = EmailMessage()
+    msg["From"] = formataddr((from_name, from_address))
+    msg["To"] = to_address
+    msg["Subject"] = subject
+    msg["Date"] = formatdate(localtime=True)
+    # If the caller didn't pin a Message-ID domain, derive it from the
+    # From address. `make_msgid` accepts None and falls back to the
+    # local hostname, which is the wrong shape for a deliverable
+    # message (the hostname might be `gke-pool-xxx`); a deployment
+    # without a configured From would surface that as a build-time
+    # config error elsewhere, so the fallback here is just defensive.
+    if msgid_domain is None:
+        if "@" in from_address:
+            msgid_domain = from_address.split("@", 1)[1]
+        else:
+            msgid_domain = "localhost"
+    msg["Message-ID"] = make_msgid(domain=msgid_domain)
+    if reply_to:
+        msg["Reply-To"] = reply_to
+    if is_transactional:
+        # RFC 3834: prevents auto-responders (vacation replies, etc.)
+        # from triggering on this message. Every kind of mail rfc-app
+        # sends today is transactional in this sense.
+        msg["Auto-Submitted"] = "auto-generated"
+    if unsubscribe_mailto or unsubscribe_url:
+        parts: list[str] = []
+        if unsubscribe_mailto:
+            parts.append(f"<mailto:{unsubscribe_mailto}>")
+        if unsubscribe_url:
+            parts.append(f"<{unsubscribe_url}>")
+        msg["List-Unsubscribe"] = ", ".join(parts)
+        if unsubscribe_url:
+            # RFC 8058 one-click. Gmail and Yahoo POST the payload
+            # `List-Unsubscribe=One-Click` to the URL on the user's
+            # one-click action; the matching POST endpoint must be
+            # idempotent and not require auth. See
+            # `api_notifications.py` for the receiver.
+            msg["List-Unsubscribe-Post"] = "List-Unsubscribe=One-Click"
+    if body_html is not None:
+        # I3 (security-audit-0026): the multipart/alternative HTML path
+        # is intentionally NOT enabled. No send path passes `body_html`
+        # today, and emitting an HTML body built from user-supplied
+        # content without escaping it first would reintroduce the C1
+        # stored-XSS class in the mail channel (the recipient's client
+        # renders the HTML). Fail loudly here rather than silently
+        # shipping HTML: enabling HTML mail is a deliberate change that
+        # MUST HTML-escape user content at the call site and remove this
+        # guard together. The text/plain path below is the only live one.
+        raise NotImplementedError(
+            "HTML email is not enabled (security-audit-0026 I3): do not "
+            "pass body_html until user content is HTML-escaped at the "
+            "call site and this guard is intentionally removed."
+        )
+    msg.set_content(body_plain)
+    return msg

backend/app/email_invite.py

@@ -0,0 +1,166 @@
+"""Outbound admin-invite email — a thin wrapper over the existing SMTP layer.
+
+v0.17.0 / roadmap item #16: when an admin uses `POST /api/admin/users` to
+create-with-invite, this module composes and sends the invite envelope.
+
+Structurally distinct from:
+
+  * `email_otc.py` (v0.7.0) — that one carries a credential the user
+    just requested; this one carries a credential the admin is sending
+    unsolicited.
+  * `email.py` (§15.4 notification mailer) — that one is inbox-driven,
+    bundled, with category opt-outs; this one is a single transactional
+    outbound to a person who does not yet have an inbox.
+  * v0.9.0's `new_beta_request` admin notification — that one is
+    invitee-to-admin (an existing pending user asking to be let in);
+    this one is admin-to-invitee (an admin reaching out to seed access).
+
+So this module reuses `EmailConfig.from_env()` for the SMTP plumbing
+and the From identity, but writes its own envelope. In dev (no
+SMTP_HOST set), the envelope is logged at INFO level and pushed to
+the same `_SENT` buffer the notification mailer uses, so the
+integration tests can assert on the outbound shape without standing
+up an SMTP server.
+
+The send is synchronous. The admin endpoint returns 200 on the
+create-row half regardless of send outcome — a transient SMTP
+failure should not roll back the invite (an admin can re-send via a
+future "resend invite" gesture, deferred to a follow-up release).
+"""
+from __future__ import annotations
+
+import logging
+import smtplib
+from email.utils import formataddr
+
+from .email import EmailConfig, _SENT, record_outbound
+from .email_envelope import build_envelope
+
+log = logging.getLogger(__name__)
+
+
+def send_invite_email(
+    *,
+    to_address: str,
+    claim_url: str,
+    inviter_display: str,
+    inviter_email: str,
+    custom_message: str = "",
+) -> bool:
+    """Compose and send the admin-invite email. Returns True on the
+    happy path; False on SMTP failure. The notifier-side buffer
+    `_SENT` is appended either way so tests can assert on content.
+
+    The body names the inviting admin, embeds the optional custom
+    message in a clearly delimited block if present, and ships the
+    claim link. The subject names the inviter so the recipient can
+    recognize the sender at a glance in their inbox preview.
+    """
+    cfg = EmailConfig.from_env()
+    subject = _subject(inviter_display, cfg)
+    body = _body(claim_url, inviter_display, inviter_email, custom_message, cfg)
+    # v0.18.0: invite mail carries a `List-Unsubscribe: <mailto:…>`
+    # only (no signed URL) — the invitee isn't a user yet, so there
+    # is no per-user opt-out row to flip. The operator handles
+    # ad-hoc opt-outs from the mailto: target. Per the proposal's
+    # "Tradeoff discussion": the invite was unsolicited from the
+    # recipient's perspective, so the courtesy header is right;
+    # but it can't be a one-click URL because the row doesn't
+    # exist yet.
+    msg = build_envelope(
+        to_address=to_address,
+        from_address=cfg.from_address,
+        from_name=cfg.from_name,
+        subject=subject,
+        body_plain=body,
+        unsubscribe_mailto=cfg.unsubscribe_mailto,
+    )
+    envelope = {
+        "to": to_address,
+        "from": formataddr((cfg.from_name, cfg.from_address)),
+        "subject": subject,
+        "body": body,
+        "kind": "invite",
+        "message": msg,
+    }
+    _SENT.append(envelope)
+
+    message_id = msg["Message-ID"]
+    if not cfg.enabled:
+        log.info("invite email disabled (EMAIL_ENABLED=0): to=%s", to_address)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="invite", status="deferred", message_id=message_id,
+        )
+        return True
+    if not cfg.smtp_host:
+        # Dev fallback: surface the claim URL at INFO so the operator can
+        # complete a claim flow without an SMTP relay. In production
+        # SMTP_HOST is always set per OHM's overlay.
+        log.info("invite email (stdout fallback): to=%s claim_url=%s", to_address, claim_url)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="invite", status="deferred", message_id=message_id,
+        )
+        return True
+
+    try:
+        smtp = smtplib.SMTP(cfg.smtp_host, cfg.smtp_port, timeout=30)
+        try:
+            if cfg.smtp_starttls:
+                smtp.starttls()
+            if cfg.smtp_user:
+                smtp.login(cfg.smtp_user, cfg.smtp_password)
+            smtp.send_message(msg)
+        finally:
+            smtp.quit()
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="invite", status="sent", message_id=message_id,
+        )
+        return True
+    except Exception as exc:
+        log.exception("invite email send failed: to=%s", to_address)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="invite", status="failed",
+            error=f"{type(exc).__name__}: {exc}", message_id=message_id,
+        )
+        return False
+
+
+def _subject(inviter_display: str, cfg: EmailConfig) -> str:
+    """e.g. "You're invited to Wiggleverse by Ben Stull"."""
+    inviter = inviter_display or "an admin"
+    return f"You're invited to {cfg.from_name} by {inviter}"
+
+
+def _body(
+    claim_url: str,
+    inviter_display: str,
+    inviter_email: str,
+    custom_message: str,
+    cfg: EmailConfig,
+) -> str:
+    inviter = inviter_display or "An admin"
+    inviter_suffix = f" ({inviter_email})" if inviter_email else ""
+    message_block = ""
+    if custom_message.strip():
+        # Indent the custom message so it reads as a clearly-delimited
+        # quote rather than running together with the framework's
+        # framing text. Per-line indent keeps multi-line messages
+        # visually grouped in plain-text mail clients.
+        indented = "\n".join(f"    {line}" for line in custom_message.strip().splitlines())
+        message_block = f"\nA personal note from {inviter}:\n\n{indented}\n"
+
+    return (
+        f"{inviter}{inviter_suffix} has invited you to {cfg.from_name}.\n"
+        f"{message_block}\n"
+        f"Click the link below to claim your account and sign in.\n"
+        f"This link is single-use and expires in 7 days.\n\n"
+        f"    {claim_url}\n\n"
+        f"If you weren't expecting this invitation, you can ignore this\n"
+        f"email — no account becomes active until you click the link.\n\n"
+        f"---\n"
+        f"{cfg.from_name} · {cfg.app_url}\n"
+    )

backend/app/email_otc.py

@@ -23,10 +23,10 @@ from __future__ import annotations
 
 import logging
 import smtplib
-from email.message import EmailMessage
 from email.utils import formataddr
 
-from .email import EmailConfig, _SENT
+from .email import EmailConfig, _SENT, record_outbound
+from .email_envelope import build_envelope
 
 log = logging.getLogger(__name__)
 
@@ -44,31 +44,48 @@ def send_otc_email(to_address: str, code: str) -> bool:
     cfg = EmailConfig.from_env()
     subject = f"Your sign-in code for {cfg.from_name}"
     body = _body(code, cfg)
+    # v0.18.0: OTC mail carries NO List-Unsubscribe — the recipient
+    # explicitly requested the code; advertising an unsubscribe
+    # header would imply OHM has them on a list, which it doesn't.
+    # See the proposal's "Tradeoff discussion" for the binding
+    # rationale.
+    msg = build_envelope(
+        to_address=to_address,
+        from_address=cfg.from_address,
+        from_name=cfg.from_name,
+        subject=subject,
+        body_plain=body,
+    )
     envelope = {
         "to": to_address,
         "from": formataddr((cfg.from_name, cfg.from_address)),
         "subject": subject,
         "body": body,
         "kind": "otc",
+        "message": msg,
     }
     _SENT.append(envelope)
 
+    message_id = msg["Message-ID"]
     if not cfg.enabled:
         log.info("otc email disabled (EMAIL_ENABLED=0): to=%s", to_address)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="otc", status="deferred", message_id=message_id,
+        )
         return True
     if not cfg.smtp_host:
         # Dev fallback: surface the code at INFO so the operator can
         # complete a sign-in flow without an SMTP relay. In production
         # SMTP_HOST is always set per OHM's overlay.
         log.info("otc email (stdout fallback): to=%s code=%s", to_address, code)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="otc", status="deferred", message_id=message_id,
+        )
         return True
 
     try:
-        msg = EmailMessage()
-        msg["From"] = envelope["from"]
-        msg["To"] = to_address
-        msg["Subject"] = subject
-        msg.set_content(body)
         smtp = smtplib.SMTP(cfg.smtp_host, cfg.smtp_port, timeout=30)
         try:
             if cfg.smtp_starttls:
@@ -78,9 +95,18 @@ def send_otc_email(to_address: str, code: str) -> bool:
             smtp.send_message(msg)
         finally:
             smtp.quit()
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="otc", status="sent", message_id=message_id,
+        )
         return True
-    except Exception:
+    except Exception as exc:
         log.exception("otc email send failed: to=%s", to_address)
+        record_outbound(
+            to_address=to_address, from_address=cfg.from_address,
+            subject=subject, kind="otc", status="failed",
+            error=f"{type(exc).__name__}: {exc}", message_id=message_id,
+        )
         return False
 
 

backend/app/entry.py

@@ -30,7 +30,7 @@ _ABSENT = object()
 class Entry:
     slug: str
     title: str
-    state: str = "super-draft"  # super-draft | active | withdrawn
+    state: str = "super-draft"  # super-draft | active | withdrawn | retired (§3, §13.7)
     id: str | None = None       # 'RFC-NNNN' or None
     repo: str | None = None
     proposed_by: str = ""
@@ -50,6 +50,13 @@ class Entry:
     # operator credentials per §18 are used. The binding is inert until
     # the named user has a funder_consents row (the hybrid two-key rule).
     funder: str | None = None
+    # §22.4c: an `active` entry that landed without a human review gate
+    # carries unreviewed=True until an owner clears it. Orthogonal to
+    # `state`; only meaningful for active entries. reviewed_at/reviewed_by
+    # are the provenance of the clear, paralleling graduated_at/by.
+    unreviewed: bool = False
+    reviewed_at: str | None = None
+    reviewed_by: str | None = None
     body: str = ""
 
 
@@ -66,6 +73,7 @@ def parse(text: str) -> Entry:
         models = [str(m) for m in raw_models]
     raw_funder = fm.get("funder")
     funder = str(raw_funder).strip() if raw_funder else None
+    unreviewed = bool(fm.get("unreviewed") or False)
     return Entry(
         slug=str(fm.get("slug") or ""),
         title=str(fm.get("title") or ""),
@@ -81,6 +89,9 @@ def parse(text: str) -> Entry:
         tags=list(fm.get("tags") or []),
         models=models,
         funder=funder,
+        unreviewed=unreviewed,
+        reviewed_at=fm.get("reviewed_at") or None,
+        reviewed_by=fm.get("reviewed_by") or None,
         body=body,
     )
 
@@ -110,6 +121,14 @@ def serialize(entry: Entry) -> str:
     # second meaning here as with `models:`; one set of semantics.
     if entry.funder:
         fm["funder"] = entry.funder
+    # §22.4c: emit unreviewed only when True (a super-draft / reviewed
+    # active entry leaves the key absent → frontmatter stays minimal).
+    if entry.unreviewed:
+        fm["unreviewed"] = True
+    if entry.reviewed_at:
+        fm["reviewed_at"] = entry.reviewed_at
+    if entry.reviewed_by:
+        fm["reviewed_by"] = entry.reviewed_by
     yaml_text = yaml.safe_dump(fm, sort_keys=False, default_flow_style=False).rstrip()
     body = entry.body.lstrip("\n")
     if body:

backend/app/funder.py

@@ -220,7 +220,7 @@ def add_consent(user_id: int, slug: str) -> None:
     db.conn().execute(
         """
         INSERT INTO funder_consents (user_id, rfc_slug) VALUES (?, ?)
-        ON CONFLICT(user_id, rfc_slug) DO NOTHING
+        ON CONFLICT(collection_id, user_id, rfc_slug) DO NOTHING
         """,
         (user_id, slug),
     )

backend/app/hygiene.py

@@ -30,7 +30,7 @@ import logging
 import os
 from datetime import datetime, timedelta, timezone
 
-from . import db
+from . import db, projects as projects_mod
 from .bot import Bot
 from .config import Config
 
@@ -284,9 +284,10 @@ async def _delete_branch_via_bot(
     reason: str,
 ) -> bool:
     """Call `bot.delete_branch` with the system actor. Resolves the
-    `(org, repo)` pair from the slug: super-draft edit branches and
-    graduation branches live on the meta repo; active-RFC branches
-    live on the per-RFC repo named by `cached_rfcs.repo`.
+    `(org, repo)` pair from the slug: under the meta-only topology (§1)
+    every meta-resident entry's edit branches and graduation branches
+    live on the meta repo; a legacy per-RFC repo (a `repo:` that survives
+    from before the fold-back, §13.6) is named by `cached_rfcs.repo`.
 
     Returns True on a clean delete; False if the rfc row is missing
     (we leave the branch row in place — a subsequent reconciler sweep
@@ -297,12 +298,20 @@ async def _delete_branch_via_bot(
     if rfc is None:
         log.warning("hygiene: cannot delete %s/%s — slug missing from cache", slug, branch)
         return False
-    if rfc["state"] == "super-draft":
-        owner, repo = config.gitea_org, config.meta_repo
-    elif rfc["state"] == "active" and rfc["repo"] and "/" in rfc["repo"]:
+    if not rfc["repo"]:
+        repo = projects_mod.default_content_repo(config)
+        if not repo:
+            log.warning(
+                "hygiene: default project has no content_repo; skipping branch delete for %s/%s",
+                slug, branch,
+            )
+            return False
+        owner = config.gitea_org
+    elif "/" in rfc["repo"]:
         owner, repo = rfc["repo"].split("/", 1)
     else:
-        log.warning("hygiene: cannot resolve repo for %s state=%s", slug, rfc["state"])
+        log.warning("hygiene: cannot resolve repo for %s state=%s repo=%r",
+                    slug, rfc["state"], rfc["repo"])
         return False
     try:
         await bot.delete_branch(

backend/app/invites.py

@@ -0,0 +1,431 @@
+"""§6.1 / v0.17.0: admin-create user with role + invite email (roadmap item #16).
+
+Distinguishes from the v0.8.0 self-serve beta-access flow:
+
+  * **Self-serve (v0.8.0)** — anyone with an email can request OTC sign-in;
+    a fresh `users` row lands in `permission_state='pending'`; an admin
+    grants or revokes via the v0.9.0 user-management page.
+
+  * **Admin-create (v0.17.0)** — an admin types first/last/email/role
+    *before* the invitee has signed in. The framework provisions the
+    `users` row with the chosen role and `permission_state='granted'`
+    (the admin's hand is the grant) and `last_seen_at IS NULL` as the
+    "invited but not yet arrived" discriminator. An invite-token row
+    lands in `user_invite_tokens`; the admin's chosen `custom_message`
+    (if any) rides in the email body alongside the claim link.
+
+  * **Claim flow** — the invitee clicks the link, which lands them at
+    `/invites/claim?token=…`. The page POSTs `/api/invites/claim` with
+    the token. The framework verifies the token (not expired, not
+    claimed, hash matches), marks the row claimed, signs the user in,
+    and returns a payload telling the frontend whether to route to
+    passcode-set (if v0.10.0 passcode flow is in play and the user has
+    no passcode yet) or to `/`. **No OTC roundtrip** — clicking the
+    unique token in the email is itself proof of email control, per
+    the roadmap. This is the intentional UX shortcut for first
+    sign-in; subsequent sign-ins use the standard OTC / passcode
+    paths.
+
+The shape:
+
+  * `create_invite(...)` — provision the invitee `users` row + the
+    `user_invite_tokens` row, return the raw token for the admin
+    endpoint to put in the outbound email link.
+  * `claim(raw_token)` — validate the token, mark it claimed, return
+    the `SessionUser` the endpoint signs in. Distinguishes the failure
+    modes (`expired`, `claimed`, `unknown`, `invalid`) so the endpoint
+    can map them to HTTP 410 vs HTTP 404 cleanly.
+  * `list_pending_invites()` — return active invites for the admin
+    listing surface. Filters out claimed + expired rows so the surface
+    only shows live invites.
+
+Token shape: opaque DB token (256 bits of CSPRNG entropy via
+`secrets.token_urlsafe(32)`), bcrypt-hashed at rest. Opaque chosen
+over JWT because revocation is then a single SQL UPDATE — a JWT
+would be stateless but harder to invalidate, and admin-issued
+invites are exactly the kind of thing an admin should be able to
+yank back. The raw token only ever lives in the outbound email link
+and the inbound claim body; server-side storage is the hash.
+
+TTL: hard-coded to 7 days via `INVITE_TOKEN_TTL_DAYS`. Env-var
+configurability is a §19.2 candidate — the constant is exposed
+here as a single point of edit if a deployment wants to override.
+
+The 500-char ceiling on `custom_message` is enforced at the
+Pydantic body level in `api_admin.py`; this module trusts what
+the endpoint hands it.
+"""
+from __future__ import annotations
+
+import logging
+import secrets
+from dataclasses import dataclass
+
+import bcrypt
+
+from . import db
+from .auth import SessionUser
+
+log = logging.getLogger(__name__)
+
+
+# ---------------------------------------------------------------------------
+# Tunables — intentionally hard-coded in v0.17.0 (§19.2 candidate to env-ify).
+# ---------------------------------------------------------------------------
+
+INVITE_TOKEN_TTL_DAYS = 7
+# 256 bits of CSPRNG entropy. `secrets.token_urlsafe(32)` yields ~43
+# URL-safe characters; the bcrypt hash is what's stored, so the raw
+# token only ever lives in the outbound email link.
+TOKEN_BYTES = 32
+# Free-text ceiling for the admin's optional custom message. Matched
+# at the Pydantic body bound in `api_admin.py`; mentioned here so the
+# bound is documented in one place.
+CUSTOM_MESSAGE_MAX_LENGTH = 500
+
+
+# ---------------------------------------------------------------------------
+# Token + hash helpers (mirror device_trust.py shape)
+# ---------------------------------------------------------------------------
+
+
+def _new_token() -> str:
+    return secrets.token_urlsafe(TOKEN_BYTES)
+
+
+def _hash(token: str) -> str:
+    return bcrypt.hashpw(token.encode("utf-8"), bcrypt.gensalt()).decode("ascii")
+
+
+def _check(token: str, token_hash: str) -> bool:
+    try:
+        return bcrypt.checkpw(token.encode("utf-8"), token_hash.encode("ascii"))
+    except (ValueError, TypeError):
+        return False
+
+
+# ---------------------------------------------------------------------------
+# Create
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class CreateOutcome:
+    """The shape returned from `create_invite`.
+
+    `raw_token` is what the admin endpoint puts in the outbound email
+    link; it never appears in storage. `invite_id` is the surrogate
+    key for the admin's "invites I've sent" listing. `invited_user_id`
+    is the freshly-provisioned `users` row id so the admin surface can
+    join through to the user-management page.
+    """
+    raw_token: str
+    invite_id: int
+    invited_user_id: int
+
+
+def create_invite(
+    *,
+    email: str,
+    first_name: str,
+    last_name: str,
+    role: str,
+    custom_message: str,
+    created_by_admin_id: int,
+) -> CreateOutcome:
+    """Provision the invitee `users` row + the `user_invite_tokens` row.
+
+    Caller (`api_admin.py`) is responsible for the admin-only auth check,
+    the self-email refusal (422), and the duplicate-email refusal (409).
+    This function trusts what it's handed and writes both rows
+    transactionally — the v0.10.0 `passcode.py` / v0.11.0 `device_trust.py`
+    helpers follow the same separation-of-concerns pattern.
+
+    The invitee `users` row is provisioned with:
+      * `permission_state='granted'` — the admin's hand is the grant;
+        the v0.8.0 self-serve `pending` queue is for the other path.
+      * `created_at` / `last_seen_at` — NOT set here, so both fall
+        through to the column default `datetime('now')` (the column is
+        `NOT NULL`; see `migrations/001_users_and_audit.sql` and the
+        longer note below). The "invited but not yet arrived" state is
+        therefore NOT carried on the user row — it is the existence of
+        an unclaimed `user_invite_tokens` row, surfaced as the listing's
+        `pending_invite` field. Consumers that want a truthful
+        last-seen MUST treat a pending-invite row as never-seen rather
+        than trusting `last_seen_at` (every real sign-in path stamps it
+        to now, but an unclaimed invite has never hit one).
+      * `gitea_id = NULL`, `gitea_login = NULL` — same as a v0.7.0
+        OTC-provisioned user; the OAuth identity is grandfathered if
+        the user ever lands through that path.
+      * `display_name` defaults to "<first> <last>" (or local-part of
+        email if both are empty) so the user-management page reads a
+        sensible label before the user has signed in.
+      * `first_name` / `last_name` / `beta_request_reason` — the
+        first two from the admin's typed values; reason stays blank
+        (this user did not self-request access).
+    """
+    email_clean = email.strip()
+    first_clean = (first_name or "").strip()
+    last_clean = (last_name or "").strip()
+    display = " ".join(p for p in (first_clean, last_clean) if p).strip()
+    if not display:
+        display = email_clean.split("@", 1)[0] or email_clean
+
+    # 1. Provision the invitee users row. The grant is the admin's
+    # hand; no permission_events row is necessary for the grant itself
+    # (we are not transitioning from pending → granted, we are landing
+    # a fresh row directly into granted).
+    #
+    # Note on the "pending invite" discriminator: the brief floated
+    # `first_sign_in_at NULL` / `last_seen_at NULL` as the marker the
+    # admin user-management page reads off the row to render the
+    # "(pending invite)" badge. The schema didn't cooperate — the
+    # existing `users.last_seen_at` column is NOT NULL with a
+    # `datetime('now')` default (see `migrations/001_users_and_audit.sql`),
+    # and there is no `first_sign_in_at` column. Rather than introduce
+    # a schema migration to add one (the brief explicitly said "likely
+    # no `users` table changes"), the discriminator is the existence of
+    # an active row in `user_invite_tokens` joined on `invited_user_id`.
+    # The admin listing's `pending_invite` field joins through that
+    # table; the claim flow stamps `claimed_at` on the invite row,
+    # which clears the badge naturally. This shape keeps the
+    # discriminator scoped to the v0.17.0 surface and avoids
+    # double-tracking against an existing column.
+    cur = db.conn().execute(
+        """
+        INSERT INTO users (
+            gitea_id, gitea_login, email, display_name, avatar_url,
+            role, permission_state, first_name, last_name
+        )
+        VALUES (NULL, NULL, ?, ?, '', ?, 'granted', ?, ?)
+        """,
+        (email_clean, display, role, first_clean, last_clean),
+    )
+    invited_user_id = cur.lastrowid
+
+    # 2. Mint the token, hash it, write the invite row.
+    raw = _new_token()
+    h = _hash(raw)
+    cur = db.conn().execute(
+        f"""
+        INSERT INTO user_invite_tokens (
+            email, role, first_name, last_name, custom_message,
+            token_hash, expires_at, created_by_admin_id, invited_user_id
+        )
+        VALUES (?, ?, ?, ?, ?, ?, datetime('now', '+{INVITE_TOKEN_TTL_DAYS} days'), ?, ?)
+        """,
+        (
+            email_clean,
+            role,
+            first_clean,
+            last_clean,
+            (custom_message or "").strip(),
+            h,
+            created_by_admin_id,
+            invited_user_id,
+        ),
+    )
+    invite_id = cur.lastrowid
+    return CreateOutcome(
+        raw_token=raw,
+        invite_id=invite_id,
+        invited_user_id=invited_user_id,
+    )
+
+
+# ---------------------------------------------------------------------------
+# Claim
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class ClaimOutcome:
+    """The result of `claim`.
+
+    `user` is populated only on success. `reason` distinguishes the
+    failure modes so the endpoint can return distinct HTTP statuses
+    (HTTP 410 for expired/claimed — the token is dead; HTTP 400 for
+    unknown/invalid — the request shape is wrong).
+    """
+    ok: bool
+    user: SessionUser | None
+    reason: str  # 'ok' | 'invalid' | 'unknown' | 'expired' | 'claimed'
+    invite_id: int | None = None
+
+
+def claim(raw_token: str) -> ClaimOutcome:
+    """Validate the presented token and consume it.
+
+    Walks the active invite rows looking for a bcrypt hash match.
+    Mirrors `device_trust.lookup`: bcrypt's per-row salt means we
+    cannot SELECT by hash, but the set is small (a deployment's
+    outstanding invites at any moment) and bcrypt is cheap on the
+    order of milliseconds.
+
+    On a hit:
+      * Mark the row claimed (stamp `claimed_at = now`,
+        `claimed_by_user_id = invited_user_id` — the admin's
+        pre-provisioned row is the claimant).
+      * Stamp `last_seen_at = now` on the user row so the v0.9.0
+        admin user-management page no longer shows "(pending invite)".
+      * Return a populated `SessionUser` for the endpoint to sign in.
+
+    On a miss:
+      * `unknown` — no row matched. The token may have been forged or
+        the invite was admin-revoked.
+      * `expired` — row matched but `expires_at` is in the past.
+      * `claimed` — row matched but `claimed_at` is non-NULL. The
+        token was already consumed; the user must contact the admin
+        for a fresh invite.
+      * `invalid` — the token string itself was empty or unparseable.
+    """
+    raw = (raw_token or "").strip()
+    if not raw:
+        return ClaimOutcome(ok=False, user=None, reason="invalid")
+
+    rows = db.conn().execute(
+        """
+        SELECT id, token_hash, expires_at, claimed_at, invited_user_id, role
+          FROM user_invite_tokens
+         ORDER BY id DESC
+        """
+    ).fetchall()
+
+    matched = None
+    for row in rows:
+        if _check(raw, row["token_hash"]):
+            matched = row
+            break
+
+    if matched is None:
+        return ClaimOutcome(ok=False, user=None, reason="unknown")
+
+    if matched["claimed_at"] is not None:
+        return ClaimOutcome(
+            ok=False, user=None, reason="claimed", invite_id=matched["id"],
+        )
+
+    expired = db.conn().execute(
+        "SELECT datetime(?) < datetime('now') AS expired",
+        (matched["expires_at"],),
+    ).fetchone()["expired"]
+    if expired:
+        return ClaimOutcome(
+            ok=False, user=None, reason="expired", invite_id=matched["id"],
+        )
+
+    # Consume the row before signing in so a parallel claim of the same
+    # token cannot double-sign-in. (Mirrors `otc.verify_code`'s consume-
+    # before-provision shape.)
+    db.conn().execute(
+        """
+        UPDATE user_invite_tokens
+           SET claimed_at = datetime('now'),
+               claimed_by_user_id = invited_user_id
+         WHERE id = ?
+        """,
+        (matched["id"],),
+    )
+    # Stamp last_seen_at on the user row so the user's activity stamp
+    # is current after the claim (mirroring otc.verify_code's
+    # last-seen update on the provision path). The "(pending invite)"
+    # badge's clear is driven by the invite row's `claimed_at`
+    # transition above; this update is for the general user-listing's
+    # recency ordering.
+    db.conn().execute(
+        "UPDATE users SET last_seen_at = datetime('now') WHERE id = ?",
+        (matched["invited_user_id"],),
+    )
+
+    user_row = db.conn().execute(
+        """
+        SELECT id, gitea_id, gitea_login, email, display_name, avatar_url,
+               role, permission_state
+          FROM users
+         WHERE id = ?
+        """,
+        (matched["invited_user_id"],),
+    ).fetchone()
+    if user_row is None:
+        # The invitee user row was deleted between create_invite and
+        # claim (shouldn't happen under the FK ON DELETE CASCADE — the
+        # cascade would drop the invite row too — be defensive anyway).
+        return ClaimOutcome(
+            ok=False, user=None, reason="unknown", invite_id=matched["id"],
+        )
+
+    return ClaimOutcome(
+        ok=True,
+        user=SessionUser(
+            user_id=user_row["id"],
+            gitea_id=user_row["gitea_id"] or 0,
+            gitea_login=user_row["gitea_login"] or "",
+            display_name=user_row["display_name"],
+            email=user_row["email"] or "",
+            avatar_url=user_row["avatar_url"] or "",
+            role=user_row["role"],
+            permission_state=user_row["permission_state"] or "granted",
+        ),
+        reason="ok",
+        invite_id=matched["id"],
+    )
+
+
+# ---------------------------------------------------------------------------
+# List pending invites — for the admin's review surface
+# ---------------------------------------------------------------------------
+
+
+@dataclass
+class PendingInviteRow:
+    """The shape the `GET /api/admin/users/invites` endpoint returns.
+
+    Note the absence of `token_hash` — the hash is structurally private,
+    and the surface has no use for it. The raw token is also not on
+    the listing; it lives only in the email link.
+    """
+    id: int
+    email: str
+    role: str
+    first_name: str
+    last_name: str
+    custom_message: str
+    created_at: str
+    expires_at: str
+    created_by_admin_id: int
+    invited_user_id: int
+
+
+def list_pending_invites() -> list[PendingInviteRow]:
+    """Active invites (not claimed, not expired), freshest first.
+
+    The admin's "I sent these but they haven't been claimed yet" view.
+    Filters mirror the `device_trust.list_for_user` shape: the surface
+    only shows live records the framework would actually accept on a
+    presented token.
+    """
+    rows = db.conn().execute(
+        """
+        SELECT id, email, role, first_name, last_name, custom_message,
+               created_at, expires_at, created_by_admin_id, invited_user_id
+          FROM user_invite_tokens
+         WHERE claimed_at IS NULL
+           AND datetime(expires_at) > datetime('now')
+         ORDER BY created_at DESC, id DESC
+        """
+    ).fetchall()
+    return [
+        PendingInviteRow(
+            id=row["id"],
+            email=row["email"],
+            role=row["role"],
+            first_name=row["first_name"] or "",
+            last_name=row["last_name"] or "",
+            custom_message=row["custom_message"] or "",
+            created_at=row["created_at"],
+            expires_at=row["expires_at"],
+            created_by_admin_id=row["created_by_admin_id"],
+            invited_user_id=row["invited_user_id"],
+        )
+        for row in rows
+    ]

backend/app/main.py

@@ -7,11 +7,12 @@ no need for a separate worker.
 from __future__ import annotations
 
 import logging
+import os
 import secrets
 from contextlib import asynccontextmanager
 
-from fastapi import APIRouter, FastAPI, HTTPException, Request
-from fastapi.responses import RedirectResponse
+from fastapi import APIRouter, FastAPI, HTTPException, Request, Response
+from fastapi.responses import JSONResponse, RedirectResponse
 from pydantic import BaseModel, Field
 from starlette.middleware.sessions import SessionMiddleware
 
@@ -20,12 +21,18 @@ from . import (
     auth,
     cache,
     db,
+    device_trust as device_trust_mod,
     digest,
     email_otc,
     hygiene,
+    invites as invites_mod,
     otc,
     passcode as passcode_mod,
+    projects,
     providers as providers_mod,
+    ratelimit,
+    registry as registry_mod,
+    turnstile,
     webhooks,
 )
 from .bot import Bot
@@ -38,11 +45,25 @@ log = logging.getLogger("rfc_app")
 
 class OtcRequestBody(BaseModel):
     email: str = Field(min_length=3, max_length=320)
+    # v0.12.0 / roadmap item #10: CloudFlare Turnstile token from the
+    # frontend widget. Optional in the body so a deployment that has
+    # not yet wired the Turnstile site key (or a dev environment with
+    # the widget intentionally skipped) still routes through the same
+    # endpoint; the backend turnstile.verify_token call decides whether
+    # to admit the request based on `TURNSTILE_REQUIRED` + presence of
+    # the secret.
+    turnstile_token: str | None = Field(default=None, max_length=4096)
 
 
 class OtcVerifyBody(BaseModel):
     email: str = Field(min_length=3, max_length=320)
     code: str = Field(min_length=1, max_length=16)
+    # v0.11.0 — "trust this device for 30 days" checkbox on the Login.jsx
+    # OTC step. When true and verify succeeds, the server issues a fresh
+    # device-trust row and sets the `rfc_device_trust` cookie on the
+    # response. Defaults to false so existing clients that don't send
+    # the flag continue to behave the way they did pre-v0.11.0.
+    trust_device: bool = False
 
 
 class PasscodeSetBody(BaseModel):
@@ -52,6 +73,27 @@ class PasscodeSetBody(BaseModel):
 class PasscodeVerifyBody(BaseModel):
     email: str = Field(min_length=3, max_length=320)
     passcode: str = Field(min_length=1, max_length=64)
+    # v0.11.0 — same trust-device opt-in as the OTC verify body.
+    trust_device: bool = False
+
+
+class InviteClaimBody(BaseModel):
+    """v0.17.0 / roadmap item #16 — claim an admin-issued invite token.
+
+    The frontend `/invites/claim?token=…` page reads the token from
+    the URL and POSTs it here. The body bound matches the
+    `secrets.token_urlsafe(32)` output shape (~43 URL-safe chars);
+    the upper bound stays generous in case `TOKEN_BYTES` is ever
+    raised. The token-shape is opaque to this layer — `invites.claim`
+    bcrypt-checks it against the active candidate set.
+    """
+    token: str = Field(min_length=1, max_length=512)
+    # v0.11.0-style opt-in: the claim flow's "trust this device" gesture
+    # is bundled here so the invitee can land trusted on first sign-in
+    # without an extra roundtrip. Defaults to false so the gesture is
+    # explicit (the frontend modal renders a checkbox alongside the
+    # claim CTA).
+    trust_device: bool = False
 
 
 @asynccontextmanager
@@ -60,6 +102,27 @@ async def lifespan(app: FastAPI):
     db.run_migrations(config)
     db.init(config)
     gitea = Gitea(config)
+    # §22.2: mirror the registry before anything reads projects/content_repo.
+    # First boot has no last-good rows, so a missing/invalid registry is fatal
+    # (loud-fail per separation-of-concerns); the reconciler sweep keeps it
+    # fresh thereafter and tolerates a later bad PR.
+    try:
+        await registry_mod.refresh_registry(config, gitea)
+    except Exception as e:
+        raise RuntimeError(
+            f"registry mirror failed at startup ({config.registry_repo_full}/projects.yaml): {e}"
+        ) from e
+    # §22.13 step 1: re-stamp the M1 bootstrap 'default' project id to the
+    # deployment's configured id (DEFAULT_PROJECT_ID) once the registry row
+    # exists, so the original corpus lands at a meaningful /p/<id>/ and
+    # 'default' is never a public URL. Idempotent no-op once done.
+    projects.restamp_default_project(config)
+    if projects.default_content_repo(config) is None:
+        raise RuntimeError(
+            f"registry does not describe the default project "
+            f"{projects.resolved_default_id(config)!r} (no content_repo). "
+            f"Add it to {config.registry_repo_full}/projects.yaml."
+        )
     bot = Bot(gitea)
     reconciler = cache.Reconciler(config, gitea)
     digest_sched = digest.DigestScheduler()
@@ -88,7 +151,7 @@ async def lifespan(app: FastAPI):
     reconciler.start()
     digest_sched.start()
     hygiene_sched.start()
-    log.info("RFC app started — meta repo %s/%s", config.gitea_org, config.meta_repo)
+    log.info("RFC app started — registry %s", config.registry_repo_full)
     try:
         yield
     finally:
@@ -104,12 +167,20 @@ def create_app() -> FastAPI:
     # eagerly via load_config(). Everything else waits for lifespan.
     config = load_config()
     app = FastAPI(lifespan=lifespan)
+    # v0.25.0 (audit 0026 M4): the session cookie is the primary 30-day
+    # auth credential and must carry `Secure` in production so it never
+    # travels cleartext. Default to Secure; a dev box serving over plain
+    # http opts out with SESSION_COOKIE_SECURE=false. Production (OHM is
+    # HTTPS-only with an HTTP->HTTPS 301) leaves this unset → Secure on.
+    session_secure = os.environ.get("SESSION_COOKIE_SECURE", "true").strip().lower() not in (
+        "0", "false", "no", "off",
+    )
     app.add_middleware(
         SessionMiddleware,
         secret_key=config.secret_key,
         session_cookie="rfc_session",
         max_age=60 * 60 * 24 * 30,
-        https_only=False,
+        https_only=session_secure,
     )
     return app
 
@@ -117,6 +188,49 @@ def create_app() -> FastAPI:
 app = create_app()
 
 
+def _set_device_trust_cookie(response: Response, cookie_value: str) -> None:
+    """Attach the v0.11.0 device-trust cookie to the response.
+
+    HttpOnly + Secure + SameSite=Lax + 30-day Max-Age + Path=/. As of
+    v0.25.0 (audit 0026 M1) the value is `IssueOutcome.cookie_value` —
+    "<row_id>.<raw_token>" — so `device_trust.lookup` can read one indexed
+    row instead of scanning; server-side storage remains the bcrypt hash
+    of the token half only. The cookie is "essential" per the v0.13.0
+    cookie-consent contract (it is part of authentication), so we set it
+    regardless of the user's analytics / other-cookies choice.
+
+    Secure=True means the cookie is only ever sent over HTTPS — the
+    device-trust cookie holds a 30-day credential and must never travel
+    cleartext. (The session cookie now also defaults to Secure; see M4 in
+    `create_app`.)
+    """
+    response.set_cookie(
+        key=device_trust_mod.COOKIE_NAME,
+        value=cookie_value,
+        max_age=device_trust_mod.COOKIE_MAX_AGE_SECONDS,
+        path="/",
+        secure=True,
+        httponly=True,
+        samesite="lax",
+    )
+
+
+def _clear_device_trust_cookie(response: Response) -> None:
+    """Delete the device-trust cookie on the response.
+
+    Used when the framework detects a presented cookie that is
+    expired, revoked, or otherwise stale — the next request from
+    this device will not carry a dead token.
+    """
+    response.delete_cookie(
+        key=device_trust_mod.COOKIE_NAME,
+        path="/",
+        secure=True,
+        httponly=True,
+        samesite="lax",
+    )
+
+
 def _oauth_router(config) -> APIRouter:
     router = APIRouter()
 
@@ -164,7 +278,31 @@ def _oauth_router(config) -> APIRouter:
     # ---------------------------------------------------------------
 
     @router.post("/auth/otc/request")
-    async def otc_request(body: OtcRequestBody):
+    async def otc_request(body: OtcRequestBody, request: Request):
+        # v0.25.0 (audit 0026 H1/L2): per-IP brake at the cheapest point,
+        # before the Turnstile network call or any bcrypt/SMTP work.
+        if not ratelimit.otc_request_limiter.allow(ratelimit.client_key(request)):
+            raise HTTPException(429, "Too many requests; please wait a few minutes")
+        # v0.12.0 / roadmap item #10: gate the request on a successful
+        # Turnstile siteverify before the bcrypt hash + SMTP send. The
+        # check runs first so a failed challenge spends no rate budget
+        # and produces no envelope. When the operator has not wired the
+        # secret AND TURNSTILE_REQUIRED=false (the default), the gate
+        # opens — see `backend/app/turnstile.py` for the full matrix.
+        client_ip = request.client.host if request.client else None
+        ts = await turnstile.verify_token(body.turnstile_token, client_ip=client_ip)
+        if not ts.ok:
+            if ts.reason == "misconfigured":
+                # TURNSTILE_REQUIRED=true but the secret is unset. This
+                # is an operator/config problem, not a client problem;
+                # surface as 500 so the operator notices in their logs
+                # rather than blaming the user's browser.
+                raise HTTPException(500, "auth misconfigured")
+            # missing-token / failed / network → uniform 400 so the
+            # response does not enumerate which leg of the challenge
+            # broke. The reason is in the server logs.
+            raise HTTPException(400, "verification failed")
+
         outcome = otc.request_code(body.email)
         if outcome.reason == "cooldown":
             # Loud failure per the rate-limit primitive — the abuse
@@ -177,10 +315,26 @@ def _oauth_router(config) -> APIRouter:
         return {"ok": True}
 
     @router.post("/auth/otc/verify")
-    async def otc_verify(body: OtcVerifyBody, request: Request):
+    async def otc_verify(body: OtcVerifyBody, request: Request, response: Response):
+        # v0.25.0 (audit 0026 H1): per-IP brake against fan-out guessing,
+        # plus the per-email lockout enforced inside otc.verify_code.
+        ip = ratelimit.client_key(request)
+        if not ratelimit.verify_limiter.allow(ip):
+            raise HTTPException(429, "Too many attempts; please wait a few minutes")
         result = otc.verify_code(body.email, body.code)
+        if result.reason == "locked":
+            raise HTTPException(
+                423,
+                {
+                    "detail": "Too many failed attempts; wait a few minutes or request a new code",
+                    "locked_until": result.locked_until,
+                },
+            )
         if not result.ok or result.user is None:
             raise HTTPException(400, "Invalid or expired code")
+        # Legit sign-in: clear this IP's window so a user who fat-fingered
+        # a couple of codes isn't left throttled.
+        ratelimit.verify_limiter.reset(ip)
         auth.store_session(request, result.user)
         # v0.8.0: surface `needs_profile` so the Login.jsx surface can
         # decide whether to advance to the first/last/why capture step
@@ -202,6 +356,18 @@ def _oauth_router(config) -> APIRouter:
             and not last_name
             and not beta_request_reason
         )
+        # v0.11.0 — opt-in device trust. The checkbox lives on the
+        # Login.jsx OTC step; when true, the server mints a fresh
+        # device-trust row and sets the long-lived cookie. The cookie
+        # is "essential" per the v0.13.0 consent contract (it is part
+        # of authentication, not analytics) so it lands regardless of
+        # the user's analytics / other-cookies choice. We capture the
+        # User-Agent at issuance so the /settings/devices surface can
+        # render a rough device label.
+        if body.trust_device:
+            ua = request.headers.get("user-agent", "")
+            outcome = device_trust_mod.issue(result.user.user_id, ua)
+            _set_device_trust_cookie(response, outcome.cookie_value)
         return {
             "ok": True,
             "user": {
@@ -225,12 +391,17 @@ def _oauth_router(config) -> APIRouter:
     # ---------------------------------------------------------------
 
     @router.get("/auth/passcode/check")
-    async def passcode_check(email: str = ""):
+    async def passcode_check(request: Request, email: str = ""):
         """Does this email have a passcode set? Anonymous endpoint —
         the Login.jsx flow calls this after the user types their email
         to decide whether to render a passcode input or fall back to
         OTC. We surface only the boolean; lockout state, the hash, and
-        the set-at stamp are not leaked here."""
+        the set-at stamp are not leaked here.
+
+        v0.25.0 (audit 0026 L3): per-IP rate limit so the has-passcode
+        boolean can't be bulk-harvested to enumerate accounts."""
+        if not ratelimit.check_limiter.allow(ratelimit.client_key(request)):
+            raise HTTPException(429, "Too many requests; please wait a few minutes")
         status = passcode_mod.passcode_status(email)
         return {"has_passcode": status.has_passcode}
 
@@ -254,12 +425,21 @@ def _oauth_router(config) -> APIRouter:
         return {"ok": True}
 
     @router.post("/auth/passcode/verify")
-    async def passcode_verify(body: PasscodeVerifyBody, request: Request):
+    async def passcode_verify(body: PasscodeVerifyBody, request: Request, response: Response):
         """Sign in with email + passcode. Returns the standard session
         payload on success; HTTP 423 with `locked_until` when the
         account is in the lockout window; HTTP 400 for every other
         failure (the wrong-vs-unknown distinction is intentionally
-        collapsed so a probing client cannot enumerate emails)."""
+        collapsed so a probing client cannot enumerate emails).
+
+        v0.11.0: the body's `trust_device` flag, if true, mints a
+        fresh device-trust row and sets the long-lived cookie. Same
+        opt-in contract as `/auth/otc/verify`."""
+        # v0.25.0 (audit 0026 H1): per-IP brake in front of the per-account
+        # passcode lockout, so fan-out across emails is throttled too.
+        ip = ratelimit.client_key(request)
+        if not ratelimit.verify_limiter.allow(ip):
+            raise HTTPException(429, "Too many attempts; please wait a few minutes")
         result = passcode_mod.verify_passcode(body.email, body.passcode)
         if result.reason == "locked":
             raise HTTPException(
@@ -271,7 +451,12 @@ def _oauth_router(config) -> APIRouter:
             )
         if not result.ok or result.user is None:
             raise HTTPException(400, "Invalid passcode")
+        ratelimit.verify_limiter.reset(ip)
         auth.store_session(request, result.user)
+        if body.trust_device:
+            ua = request.headers.get("user-agent", "")
+            outcome = device_trust_mod.issue(result.user.user_id, ua)
+            _set_device_trust_cookie(response, outcome.cookie_value)
         return {
             "ok": True,
             "user": {
@@ -282,4 +467,151 @@ def _oauth_router(config) -> APIRouter:
             },
         }
 
+    # ---------------------------------------------------------------
+    # v0.17.0: admin-create user + invite claim (§6.1, roadmap item #16).
+    #
+    # The admin-create surface lives at POST /api/admin/users (see
+    # api_admin.py); this endpoint is the corresponding claim path the
+    # invitee hits when they click the link in their invite email.
+    # The frontend route `/invites/claim?token=…` reads the token from
+    # the URL and POSTs it here.
+    #
+    # The claim itself is the first-sign-in for the invitee: clicking
+    # the unique token in the email is proof of email control per the
+    # roadmap, so this endpoint skips the OTC step entirely on first
+    # sign-in. The session cookie lands; the response tells the
+    # frontend whether to route to passcode-set (if v0.10.0 passcode
+    # flow is in play and the user has not yet set a passcode) or to
+    # home.
+    #
+    # The endpoint is anonymous-reachable: the entire point is to
+    # establish the session, so we do not gate it on `require_user`.
+    # The trust-device opt-in mirrors the v0.11.0 OTC/passcode verify
+    # contract (the body's `trust_device` flag, when true, mints a
+    # fresh device-trust row on the same response so the invitee
+    # lands trusted on their first device).
+    # ---------------------------------------------------------------
+
+    @router.post("/api/invites/claim")
+    async def invites_claim(body: InviteClaimBody, request: Request, response: Response):
+        result = invites_mod.claim(body.token)
+        if result.reason == "expired":
+            # The token's TTL window passed without a claim. HTTP 410
+            # (Gone) so the frontend can render a "this invite has
+            # expired — please contact the admin for a fresh one"
+            # message distinct from the generic invalid-token shape.
+            raise HTTPException(410, "This invite has expired")
+        if result.reason == "claimed":
+            # The token was already consumed. HTTP 410 for the same
+            # reason — the row is dead either way.
+            raise HTTPException(410, "This invite has already been claimed")
+        if not result.ok or result.user is None:
+            # 'unknown' / 'invalid' — the token does not match any
+            # active invite row. HTTP 400 so it reads distinct from
+            # the dead-token shape above.
+            raise HTTPException(400, "Invalid invite token")
+
+        # Establish the session. From here on the invitee is signed
+        # in as the pre-provisioned user row carrying their
+        # pre-assigned role.
+        auth.store_session(request, result.user)
+
+        # v0.11.0 — opt-in device trust on the claim response. Same
+        # contract as OTC/passcode verify: when the body's flag is
+        # true, the server mints a fresh device-trust row and sets
+        # the long-lived cookie, so the invitee skips the email step
+        # on subsequent visits to the same browser.
+        if body.trust_device:
+            ua = request.headers.get("user-agent", "")
+            outcome = device_trust_mod.issue(result.user.user_id, ua)
+            _set_device_trust_cookie(response, outcome.cookie_value)
+
+        # Has the user already set a passcode? (Could only happen via
+        # an admin pre-population path that doesn't exist yet, but
+        # the response shape mirrors `/api/auth/me` so the frontend
+        # can read it without a second call.) If `needs_passcode` is
+        # true and v0.10.0 passcode flow is in play, the frontend
+        # routes to /settings/notifications#sign-in to set a passcode
+        # immediately; otherwise it routes to /.
+        row = db.conn().execute(
+            "SELECT passcode_hash FROM users WHERE id = ?",
+            (result.user.user_id,),
+        ).fetchone()
+        has_passcode = bool(row and row["passcode_hash"])
+
+        return {
+            "ok": True,
+            "user": {
+                "id": result.user.user_id,
+                "display_name": result.user.display_name,
+                "email": result.user.email,
+                "role": result.user.role,
+                "permission_state": result.user.permission_state,
+            },
+            # Roadmap §16: the claim flow skips OTC entirely; the
+            # natural next step is passcode-set (so the invitee can
+            # sign back in without needing an email roundtrip on their
+            # second visit). The frontend uses this hint to decide
+            # whether to route to the passcode-set screen or to home.
+            "needs_passcode": not has_passcode,
+        }
+
+    # ---------------------------------------------------------------
+    # v0.11.0: trust device for 30 days (§6.2, roadmap item #9).
+    #
+    # The /auth/device-trust/start endpoint resolves a presented
+    # `rfc_device_trust` cookie. If it matches a non-expired,
+    # non-revoked row, the session is re-established and the client
+    # is told to skip OTC/passcode entry. A stale cookie (expired or
+    # revoked) is cleared on the response. A miss is structurally
+    # silent — the client falls back to the email step.
+    #
+    # The endpoint is anonymous-reachable: a returning visitor with
+    # the cookie hits this before the email step. We do not gate it
+    # on a session because the entire point is to establish one.
+    # ---------------------------------------------------------------
+
+    @router.post("/auth/device-trust/start")
+    async def device_trust_start(request: Request):
+        """Sign in via a presented device-trust cookie.
+
+        On a hit, re-establishes the session in the cookie store and
+        returns a user payload shaped like /auth/otc/verify (minus
+        `needs_profile`, which a returning device-trust user is
+        structurally past — they signed in at least once before).
+        On a miss, returns 401 + clears the stale cookie. An
+        'unknown' miss (cookie present but no row matches) also
+        clears, since the token is dead to the server either way.
+
+        Note on response construction: we return a `JSONResponse`
+        directly rather than raising `HTTPException` on the miss
+        path because FastAPI's exception handler builds a new
+        response from scratch and would drop any `set_cookie` /
+        `delete_cookie` calls. The hand-built `JSONResponse` lets
+        us attach the cookie-clear header alongside the 401.
+        """
+        raw = request.cookies.get(device_trust_mod.COOKIE_NAME, "")
+        if not raw:
+            return JSONResponse({"detail": "No device trust"}, status_code=401)
+        outcome = device_trust_mod.lookup(raw)
+        if not outcome.ok or outcome.user is None:
+            # Clear the stale cookie so subsequent requests don't
+            # keep replaying a dead token. We surface 401 in all
+            # cases so a probing client can't tell "your row was
+            # revoked" from "this token never existed".
+            response = JSONResponse({"detail": "Device trust invalid"}, status_code=401)
+            _clear_device_trust_cookie(response)
+            return response
+        auth.store_session(request, outcome.user)
+        return {
+            "ok": True,
+            "user": {
+                "id": outcome.user.user_id,
+                "display_name": outcome.user.display_name,
+                "email": outcome.user.email,
+                "role": outcome.user.role,
+                "permission_state": outcome.user.permission_state,
+            },
+        }
+
     return router

backend/app/notify.py

@@ -270,6 +270,86 @@ def fan_out_new_beta_request(
         )
 
 
+def fan_out_contribution_request(
+    *,
+    rfc_slug: str,
+    requester_user_id: int,
+    request_id: int,
+    matched_term: str,
+    who_i_am: str,
+    why: str,
+    use_case: str | None,
+) -> list[int]:
+    """Roadmap #28 Part 3: a reader asked to contribute to a pending
+    (super-draft) RFC. Land one actionable notification per owner and
+    return their ids (the caller stamps the first onto the request row as
+    the inbox-action handle).
+
+    Personal-direct: the owner is the named subject of the request, so the
+    §15.4 email gate consults `email_personal_direct` exactly as for the
+    other owner-facing personal events — no new preference column is
+    needed. The request's three free-text fields ride along in the payload
+    so the inbox row can show the full ask inline without a second fetch.
+    Actor is the requester per §15.9.
+    """
+    requester = db.conn().execute(
+        "SELECT display_name FROM users WHERE id = ?", (requester_user_id,)
+    ).fetchone()
+    display = (requester["display_name"] if requester else None) or "Someone"
+    details = {
+        "request_id": request_id,
+        "matched_term": matched_term,
+        "requester_user_id": requester_user_id,
+        "requester_display": display,
+        "who_i_am": who_i_am,
+        "why": why,
+        "use_case": use_case or "",
+    }
+    notif_ids: list[int] = []
+    for recipient_id in _entry_owner_user_ids(rfc_slug):
+        if recipient_id == requester_user_id:
+            continue
+        notif_ids.append(
+            _emit_one(
+                recipient_user_id=recipient_id,
+                event_kind="contribution_request_on_pending_rfc",
+                category=CATEGORY_PERSONAL,
+                actor_user_id=requester_user_id,
+                rfc_slug=rfc_slug,
+                branch_name=None,
+                pr_number=None,
+                details=details,
+            )
+        )
+    return notif_ids
+
+
+def notify_contribution_decided(
+    *,
+    rfc_slug: str,
+    requester_user_id: int,
+    decider_user_id: int,
+    request_id: int,
+    accepted: bool,
+) -> None:
+    """Roadmap #28 Part 3: tell the requester an owner accepted or declined
+    their contribute request. On accept the requester also receives the
+    #12 invitation email out-of-band; this inbox row is the in-app echo
+    that points them at it."""
+    _emit_one(
+        recipient_user_id=requester_user_id,
+        event_kind=(
+            "contribution_request_accepted" if accepted else "contribution_request_declined"
+        ),
+        category=CATEGORY_PERSONAL,
+        actor_user_id=decider_user_id,
+        rfc_slug=rfc_slug,
+        branch_name=None,
+        pr_number=None,
+        details={"request_id": request_id},
+    )
+
+
 def fan_out_chat_message(
     *,
     actor_user_id: int,
@@ -769,6 +849,16 @@ def render_summary(event_kind: str, actor_display: str | None, rfc_title: str |
         return f"{actor} began graduating {title}."
     if event_kind == "pr_conflict_with_main":
         return f"{actor} started a resolution branch on {title}."
+    if event_kind == "contribution_request_on_pending_rfc":
+        # Roadmap #28 Part 3: owner-facing, actionable. The term is the
+        # super-draft reference that surfaced the offer; the inbox row
+        # renders Accept/Decline beneath this line.
+        term = extras.get("matched_term") or title
+        return f"{actor} wants to contribute to your pending RFC for '{term}'."
+    if event_kind == "contribution_request_accepted":
+        return f"{actor} accepted your request to contribute to {title} — check your email to accept the invitation."
+    if event_kind == "contribution_request_declined":
+        return f"{actor} declined your request to contribute to {title}."
     if event_kind == "new_beta_request":
         # v0.9.0: framework-scoped, not RFC-scoped. The actor (the
         # requester) and the captured full name + email read as
@@ -884,6 +974,11 @@ def list_inbox(
             "read_at": row["read_at"],
             "category": extras.get("category"),
             "summary": render_summary(row["event_kind"], row["actor_display"], row["rfc_title"], extras),
+            # The row's payload, surfaced for kinds that render inline
+            # detail (e.g. #28 Part 3's contribute-request who/why/use-case
+            # + Accept/Decline). Safe to expose: a recipient only ever sees
+            # their own notifications.
+            "extras": extras,
         })
 
     if bundled:

backend/app/otc.py

@@ -85,6 +85,15 @@ def _cooldown_seconds() -> int:
         return 60
 
 
+# v0.25.0 / security audit 0026 (H1): per-email OTC verify lockout,
+# mirroring the passcode path (passcode.py). Five consecutive wrong codes
+# for an email lock its OTC verify for 15 minutes. The per-IP limiter in
+# ratelimit.py is the primary brute-force brake; this is the durable,
+# passcode-parity layer.
+LOCKOUT_AFTER_FAILED_ATTEMPTS = 5
+LOCKOUT_DURATION_MINUTES = 15
+
+
 # ---------------------------------------------------------------------------
 # Code generation + hashing
 # ---------------------------------------------------------------------------
@@ -206,6 +215,61 @@ class VerifyOutcome:
     ok: bool
     user: SessionUser | None
     reason: str
+    # v0.25.0 (H1): ISO-8601 stamp when reason == 'locked'.
+    locked_until: str | None = None
+
+
+def _verify_lockout_until(email: str) -> str | None:
+    """Return the active lockout stamp for `email`, or None if not locked.
+
+    Clears an elapsed lockout (and resets the counter) as a side effect so
+    the next failure starts a fresh budget — mirrors passcode.verify_passcode.
+    """
+    row = db.conn().execute(
+        "SELECT failed_attempts, locked_until FROM otc_verify_state WHERE email = ?",
+        (email,),
+    ).fetchone()
+    if row is None or not row["locked_until"]:
+        return None
+    still_locked = db.conn().execute(
+        "SELECT datetime(?) > datetime('now') AS locked", (row["locked_until"],),
+    ).fetchone()["locked"]
+    if still_locked:
+        return row["locked_until"]
+    db.conn().execute(
+        "UPDATE otc_verify_state SET failed_attempts = 0, locked_until = NULL WHERE email = ?",
+        (email,),
+    )
+    return None
+
+
+def _record_verify_failure(email: str) -> None:
+    """Increment the per-email failure counter; stamp a lockout once it
+    crosses the threshold. Mirrors the passcode lockout shape."""
+    db.conn().execute(
+        """
+        INSERT INTO otc_verify_state (email, failed_attempts)
+        VALUES (?, 1)
+        ON CONFLICT(email) DO UPDATE SET failed_attempts = failed_attempts + 1
+        """,
+        (email,),
+    )
+    count = db.conn().execute(
+        "SELECT failed_attempts FROM otc_verify_state WHERE email = ?", (email,),
+    ).fetchone()["failed_attempts"]
+    if count >= LOCKOUT_AFTER_FAILED_ATTEMPTS:
+        db.conn().execute(
+            f"""
+            UPDATE otc_verify_state
+               SET locked_until = datetime('now', '+{LOCKOUT_DURATION_MINUTES} minutes')
+             WHERE email = ?
+            """,
+            (email,),
+        )
+
+
+def _clear_verify_state(email: str) -> None:
+    db.conn().execute("DELETE FROM otc_verify_state WHERE email = ?", (email,))
 
 
 def verify_code(email: str, code: str) -> VerifyOutcome:
@@ -214,6 +278,13 @@ def verify_code(email: str, code: str) -> VerifyOutcome:
     if not email or not code:
         return VerifyOutcome(ok=False, user=None, reason="invalid")
 
+    # v0.25.0 (H1): refuse before spending any bcrypt if this email is in
+    # its OTC-verify lockout window. The passcode path is unaffected — a
+    # locked-out OTC user can still set/use a passcode, and vice versa.
+    locked_until = _verify_lockout_until(email)
+    if locked_until:
+        return VerifyOutcome(ok=False, user=None, reason="locked", locked_until=locked_until)
+
     rows = db.conn().execute(
         """
         SELECT id, code_hash, expires_at, consumed_at
@@ -237,6 +308,9 @@ def verify_code(email: str, code: str) -> VerifyOutcome:
             break
 
     if matched is None:
+        # A genuine wrong guess against this email — the brute-force
+        # signal. Count it toward the lockout threshold (H1).
+        _record_verify_failure(email)
         return VerifyOutcome(ok=False, user=None, reason="wrong")
 
     if matched["consumed_at"] is not None:
@@ -255,6 +329,8 @@ def verify_code(email: str, code: str) -> VerifyOutcome:
         "UPDATE otc_codes SET consumed_at = datetime('now') WHERE id = ?",
         (matched["id"],),
     )
+    # Success wipes the per-email failure counter (H1).
+    _clear_verify_state(email)
     user = provision_or_link_user(email)
     return VerifyOutcome(ok=True, user=user, reason="ok")
 

backend/app/projects.py

@@ -0,0 +1,122 @@
+"""Project registry — the §22 multi-project layer.
+
+A deployment hosts one or more projects (§22.1). The git registry mirror
+that lets a deployment declare projects lands in M3 and drives this module.
+`seed_default_project` (the §22.13 META_REPO backfill) is retired in M3;
+the registry mirror (`registry.refresh_registry`) is authoritative.
+"""
+from __future__ import annotations
+
+import logging
+
+from . import db
+from .config import Config
+
+log = logging.getLogger(__name__)
+
+DEFAULT_PROJECT_ID = "default"
+
+
+def resolved_default_id(config: Config) -> str:
+    """The id of the deployment's bootstrap/default project. Plan A: always
+    'default' (the re-stamp to a config slug rides Plan B). The config knob is
+    read here so Plan B can flip the resolution without touching call sites."""
+    return config.default_project_id.strip() or DEFAULT_PROJECT_ID
+
+
+def restamp_default_project(config: Config) -> None:
+    """§22.13 step 1 — one-time rename of the M1 bootstrap project id
+    (DEFAULT_PROJECT_ID = 'default') to the deployment's configured default id
+    (the DEFAULT_PROJECT_ID env var, e.g. 'ohm'), so the deployment's original
+    corpus lands at a meaningful `/p/<id>/` and `default` is never a public URL.
+
+    Renames `project_id` across every project-scoped table (discovered by
+    column, so it stays correct as the schema grows), then drops the stale
+    bootstrap `projects` row (its data has moved to the configured row, which
+    the registry mirror already created). Idempotent and a no-op when the
+    configured id is still 'default' or no bootstrap rows remain. Runs at
+    startup after the registry mirror, with FK enforcement off for the rename
+    (the composite FKs are kept consistent because parent and child rows are
+    renamed together) and a foreign_key_check backstop before commit.
+    """
+    target = resolved_default_id(config)
+    if target == DEFAULT_PROJECT_ID:
+        return
+    conn = db.conn()
+    # §22 three-tier: the entry-corpus tables key on collection_id now; detect a
+    # lingering bootstrap project by the project-grain `collections.project_id`
+    # (the PRAGMA scan below still renames every project_id column dynamically).
+    has_rows = conn.execute(
+        "SELECT 1 FROM collections WHERE project_id = ? LIMIT 1", (DEFAULT_PROJECT_ID,)
+    ).fetchone()
+    stale_proj = conn.execute(
+        "SELECT 1 FROM projects WHERE id = ? LIMIT 1", (DEFAULT_PROJECT_ID,)
+    ).fetchone()
+    if not has_rows and not stale_proj:
+        return
+    if conn.execute("SELECT 1 FROM projects WHERE id = ? LIMIT 1", (target,)).fetchone() is None:
+        log.warning("restamp: target project %r not in registry yet; skipping", target)
+        return
+
+    tables = [r["name"] for r in conn.execute("SELECT name FROM sqlite_master WHERE type='table'")]
+    pid_tables = [
+        t for t in tables
+        if any(c["name"] == "project_id" for c in conn.execute(f"PRAGMA table_info({t})"))
+    ]
+    conn.execute("PRAGMA foreign_keys = OFF")
+    try:
+        conn.execute("BEGIN")
+        for t in pid_tables:
+            conn.execute(
+                f"UPDATE {t} SET project_id = ? WHERE project_id = ?",
+                (target, DEFAULT_PROJECT_ID),
+            )
+        # The bootstrap row's data has moved to the configured (registry) row.
+        conn.execute("DELETE FROM projects WHERE id = ?", (DEFAULT_PROJECT_ID,))
+        violations = conn.execute("PRAGMA foreign_key_check").fetchall()
+        if violations:
+            conn.execute("ROLLBACK")
+            raise RuntimeError(
+                f"restamp left foreign-key violations: {[tuple(v) for v in violations]}"
+            )
+        conn.execute("COMMIT")
+    except Exception:
+        try:
+            conn.execute("ROLLBACK")
+        except Exception:
+            pass
+        raise
+    finally:
+        conn.execute("PRAGMA foreign_keys = ON")
+    log.info("restamp: renamed bootstrap project %r -> %r across %d tables",
+             DEFAULT_PROJECT_ID, target, len(pid_tables))
+
+
+def default_content_repo(config: Config) -> str | None:
+    """The content repo the single-corpus mirror reads, from the default
+    project's row (filled by the registry mirror). Replaces the retired
+    META_REPO. None until the registry mirror has run."""
+    row = db.conn().execute(
+        "SELECT content_repo FROM projects WHERE id = ?",
+        (resolved_default_id(config),),
+    ).fetchone()
+    return row["content_repo"] if row and row["content_repo"] else None
+
+
+def content_repo(project_id: str) -> str | None:
+    """The content repo for a specific project (§22.3). None if unknown/unset.
+    The per-project successor to `default_content_repo` for the write path."""
+    row = db.conn().execute(
+        "SELECT content_repo FROM projects WHERE id = ?", (project_id,)
+    ).fetchone()
+    return row["content_repo"] if row and row["content_repo"] else None
+
+
+def project_initial_state(project_id: str) -> str:
+    """§22.4b landing state for new entries in a project's default collection
+    (the per-corpus field moved down to the collection in migration 029).
+    Defaults to 'super-draft' for an unknown/unset row (today's-flow default)."""
+    from . import collections as collections_mod
+    return collections_mod.collection_initial_state(
+        collections_mod.default_collection_id(project_id)
+    )

backend/app/providers.py

@@ -184,6 +184,21 @@ def load_providers(env: dict) -> dict[str, BaseProvider]:
     return providers
 
 
+def construct_haiku(api_key: str) -> AnthropicProvider:
+    """A dedicated Claude Haiku provider, independent of the
+    `ENABLED_MODELS` chat-picker universe.
+
+    The §9.1 tag-suggestion surface (roadmap #27) always wants the
+    cheap + fast model regardless of which models the operator surfaces
+    in the §8.12 picker, so it constructs Haiku directly from the
+    operator's Anthropic key rather than going through `load_providers`.
+    The model id is sourced from the same `_CLAUDE_VARIANTS` table the
+    picker uses, so a model-string bump lands in one place.
+    """
+    model, name = _CLAUDE_VARIANTS["claude-haiku"]
+    return AnthropicProvider(api_key=api_key, model=model, display_name=name)
+
+
 def load_from_config(config) -> dict[str, BaseProvider]:
     """Convenience adapter so callers can pass our Config dataclass directly."""
     env = {

backend/app/ratelimit.py

@@ -0,0 +1,92 @@
+"""In-process per-IP sliding-window rate limiter (security audit 0026, H1).
+
+The auth verify endpoints (`/auth/otc/verify`, `/auth/passcode/verify`)
+had no per-IP brake, so an attacker could fan out guesses against a
+target identity bounded only by bcrypt cost. This module is the brake.
+
+It is deliberately tiny: §4.2 says the app is a single process with a
+colocated SQLite file, so an in-memory dict of `key -> deque[timestamps]`
+is sufficient and needs no shared store. State resets on restart, which
+fails *open* for a brief window — acceptable because the per-email OTC
+lockout (`otc_verify_state`) and the passcode lockout both persist in the
+database and carry the durable guarantee; this limiter is the
+anti-fan-out layer on top.
+
+Chosen over a per-identity lockout *as the primary control* because a
+per-IP window throttles the attacker without letting them grief a victim
+by locking that victim's account (the known downside of identity
+lockouts). Both layers run together.
+"""
+from __future__ import annotations
+
+import threading
+import time
+from collections import defaultdict, deque
+
+
+class SlidingWindowLimiter:
+    """Allow at most `max_events` per `window_seconds` per key.
+
+    `allow(key)` records an event and returns True if the key is still
+    within budget, False if it has exceeded it. Timestamps use a
+    monotonic clock so the limiter is immune to wall-clock jumps.
+    """
+
+    def __init__(self, max_events: int, window_seconds: float) -> None:
+        self.max_events = max_events
+        self.window_seconds = window_seconds
+        self._events: dict[str, deque[float]] = defaultdict(deque)
+        self._lock = threading.Lock()
+
+    def allow(self, key: str) -> bool:
+        now = time.monotonic()
+        cutoff = now - self.window_seconds
+        with self._lock:
+            q = self._events[key]
+            while q and q[0] < cutoff:
+                q.popleft()
+            if len(q) >= self.max_events:
+                return False
+            q.append(now)
+            # Opportunistic cleanup so idle keys don't accumulate forever.
+            if not q:
+                self._events.pop(key, None)
+            return True
+
+    def reset(self, key: str) -> None:
+        """Drop a key's window — e.g. after a successful sign-in so a
+        legitimate user who fat-fingered a few times isn't throttled."""
+        with self._lock:
+            self._events.pop(key, None)
+
+
+# Module-level limiters shared across requests (one process, so module
+# state is the natural home). Tunables are intentionally generous enough
+# not to bother a human retyping a code, tight enough to kill fan-out:
+#   * verify: 10 attempts / 5 min / IP across the auth verify surfaces.
+#   * otc request: 5 sends / 5 min / IP (Turnstile is the primary gate;
+#     this is defense in depth against a solved-challenge replay loop).
+verify_limiter = SlidingWindowLimiter(max_events=10, window_seconds=300)
+otc_request_limiter = SlidingWindowLimiter(max_events=5, window_seconds=300)
+# /auth/passcode/check is an anonymous has-passcode oracle (audit 0026 L3).
+# It's a legitimate Login-flow affordance, so the budget is generous —
+# enough for a human typing emails, tight enough to stop bulk scraping.
+check_limiter = SlidingWindowLimiter(max_events=30, window_seconds=300)
+
+
+def _reset_all_for_tests() -> None:
+    """Clear every module-level limiter's window. Test support only — the
+    limiters are process-global singletons, so without a per-test reset
+    one test's requests bleed into the next and later tests trip the
+    budget (429). Not called in production."""
+    for lim in (verify_limiter, otc_request_limiter, check_limiter):
+        with lim._lock:
+            lim._events.clear()
+
+
+def client_key(request) -> str:
+    """Best-effort client identity for limiting. Behind nginx the app is
+    started with `--forwarded-allow-ips 127.0.0.1`, so `request.client.host`
+    reflects the real client IP via Uvicorn's ProxyHeaders handling."""
+    client = getattr(request, "client", None)
+    return client.host if client and client.host else "unknown"

backend/app/registry.py

@@ -0,0 +1,338 @@
+"""§22.2 project registry mirror — the config-side analogue of
+cache.refresh_meta_repo.
+
+A deployment declares its projects in a `projects.yaml` at the root of
+REGISTRY_REPO. This module mirrors that file into the `projects` cache table
+and the `deployment` singleton. Per §22.2, `projects` rows flow from the
+registry only — never from user actions. The mirror runs on the registry-repo
+webhook and on every reconciler sweep (Option A wiring, Task 5).
+"""
+from __future__ import annotations
+
+import base64
+import json
+import logging
+import re
+from dataclasses import dataclass, field
+
+import yaml
+
+from . import db
+from .config import Config
+from .gitea import Gitea
+
+log = logging.getLogger(__name__)
+
+VALID_TYPES = {"document", "specification", "bdd"}
+VALID_VISIBILITY = {"gated", "public", "unlisted"}
+VALID_INITIAL_STATE = {"super-draft", "active"}
+# §22.4b: per-type default landing state.
+_TYPE_DEFAULT_INITIAL_STATE = {
+    "document": "super-draft",
+    "specification": "super-draft",
+    "bdd": "active",
+}
+_SLUG_RE = re.compile(r"^[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$")
+
+
+class RegistryError(Exception):
+    """A registry document that fails validation, or a missing registry file.
+
+    Raised by parse_registry/refresh_registry. The caller decides severity:
+    fatal at startup (no last-good to serve), tolerated on a running deployment
+    (keep the last-good projects rows). See Task 5 wiring.
+    """
+
+
+@dataclass
+class ProjectEntry:
+    id: str
+    name: str
+    type: str
+    content_repo: str
+    visibility: str
+    initial_state: str
+    config: dict = field(default_factory=dict)  # theme, enabled_models
+
+
+@dataclass
+class CollectionEntry:
+    """A named collection declared by a `.collection.yaml` manifest inside a
+    project's content repo (S2). `visibility=None` means "inherit the project's
+    visibility"."""
+    type: str
+    visibility: str | None
+    initial_state: str
+    name: str | None
+
+
+@dataclass
+class RegistryDoc:
+    deployment_name: str
+    deployment_tagline: str
+    projects: list[ProjectEntry]
+
+
+def parse_registry(text: str) -> RegistryDoc:
+    """Parse + validate projects.yaml. Pure (no I/O). Raises RegistryError."""
+    raw = yaml.safe_load(text) or {}
+    dep = raw.get("deployment") or {}
+    projects_raw = raw.get("projects") or []
+    if not isinstance(projects_raw, list) or not projects_raw:
+        raise RegistryError("registry must declare at least one project")
+    seen: set[str] = set()
+    entries: list[ProjectEntry] = []
+    for p in projects_raw:
+        if not isinstance(p, dict):
+            raise RegistryError(f"each project entry must be a mapping, got {type(p).__name__}")
+        pid = str(p.get("id") or "").strip()
+        if not _SLUG_RE.match(pid):
+            raise RegistryError(f"project id {pid!r} is not a valid slug")
+        if pid in seen:
+            raise RegistryError(f"duplicate project id {pid!r}")
+        seen.add(pid)
+        name = str(p.get("name") or "").strip()
+        if not name:
+            raise RegistryError(f"project {pid!r} missing name")
+        ptype = str(p.get("type") or "").strip()
+        if ptype not in VALID_TYPES:
+            raise RegistryError(f"project {pid!r} has invalid type {ptype!r}")
+        content_repo = str(p.get("content_repo") or "").strip()
+        if not content_repo:
+            raise RegistryError(f"project {pid!r} missing content_repo")
+        vis = str(p.get("visibility") or "gated").strip()
+        if vis not in VALID_VISIBILITY:
+            raise RegistryError(f"project {pid!r} has invalid visibility {vis!r}")
+        initial_state = str(
+            p.get("initial_state") or _TYPE_DEFAULT_INITIAL_STATE[ptype]
+        ).strip()
+        if initial_state not in VALID_INITIAL_STATE:
+            raise RegistryError(
+                f"project {pid!r} has invalid initial_state {initial_state!r}"
+            )
+        cfg: dict = {}
+        if p.get("theme") is not None:
+            cfg["theme"] = p["theme"]
+        if p.get("enabled_models") is not None:
+            cfg["enabled_models"] = [str(m) for m in p["enabled_models"]]
+        entries.append(
+            ProjectEntry(pid, name, ptype, content_repo, vis, initial_state, cfg)
+        )
+    return RegistryDoc(
+        deployment_name=str(dep.get("name") or "").strip(),
+        deployment_tagline=str(dep.get("tagline") or "").strip(),
+        projects=entries,
+    )
+
+
+def parse_collection_manifest(text: str) -> CollectionEntry:
+    """Parse + validate a `.collection.yaml`. Pure (no I/O). Raises RegistryError.
+
+    `type` is required and immutable (§22.4a, enforced at upsert). `visibility`
+    is optional — omitted means inherit the project's. `initial_state` defaults
+    per type (§22.4b)."""
+    raw = yaml.safe_load(text) or {}
+    if not isinstance(raw, dict):
+        raise RegistryError("collection manifest must be a mapping")
+    ctype = str(raw.get("type") or "").strip()
+    if ctype not in VALID_TYPES:
+        raise RegistryError(f"collection has invalid type {ctype!r}")
+    vis = raw.get("visibility")
+    if vis is not None:
+        vis = str(vis).strip()
+        if vis not in VALID_VISIBILITY:
+            raise RegistryError(f"collection has invalid visibility {vis!r}")
+    initial_state = str(
+        raw.get("initial_state") or _TYPE_DEFAULT_INITIAL_STATE[ctype]
+    ).strip()
+    if initial_state not in VALID_INITIAL_STATE:
+        raise RegistryError(f"collection has invalid initial_state {initial_state!r}")
+    name = raw.get("name")
+    name = str(name).strip() if name else None
+    return CollectionEntry(ctype, vis, initial_state, name)
+
+
+def _default_collection_id(project_id: str, default_id: str) -> str:
+    """The id of a project's default collection. The deployment's primary
+    project (== `default_id`, the §22.13 resolved default) gets the stable
+    literal `'default'` — matching migration 029's seed so the upsert *merges*
+    onto the migration-seeded row rather than duplicating it (critical on a
+    fresh deploy where the bootstrap `default` project is later restamped to the
+    configured id). Any additional project keys its default collection by its own
+    id, keeping the collection PK globally unique (pre-S5 multi-project)."""
+    return "default" if project_id == default_id else project_id
+
+
+def apply_registry(doc: RegistryDoc, registry_sha: str, default_id: str) -> None:
+    """Upsert the parsed registry into projects + their default collections +
+    the deployment singleton. Idempotent.
+
+    §22 three-tier (S1): a project carries the grouping-tier fields (name,
+    content_repo, visibility, config); the per-corpus fields (`type`,
+    `initial_state`) live on the project's default collection. §22.4a: `type` is
+    immutable — a change against an existing collection is rejected (skip the
+    type change + log), never applied. Projects absent from the registry are
+    left in place (archival is out of scope for M3; they stop refreshing).
+    """
+    with db.tx() as conn:
+        for e in doc.projects:
+            cid = _default_collection_id(e.id, default_id)
+            existing = conn.execute(
+                "SELECT type FROM collections WHERE id = ?", (cid,)
+            ).fetchone()
+            type_locked = existing is not None and existing["type"] != e.type
+            if type_locked:
+                log.error(
+                    "registry: refusing immutable type change on collection %s (%s -> %s)",
+                    cid, existing["type"], e.type,
+                )
+            # The project (grouping tier) always refreshes.
+            conn.execute(
+                """
+                INSERT INTO projects
+                    (id, name, content_repo, visibility, config_json, registry_sha, updated_at)
+                VALUES (?, ?, ?, ?, ?, ?, datetime('now'))
+                ON CONFLICT(id) DO UPDATE SET
+                    name = excluded.name,
+                    content_repo = excluded.content_repo,
+                    visibility = excluded.visibility,
+                    config_json = excluded.config_json,
+                    registry_sha = excluded.registry_sha,
+                    updated_at = datetime('now')
+                """,
+                (e.id, e.name, e.content_repo, e.visibility, json.dumps(e.config), registry_sha),
+            )
+            # The default collection (corpus tier). On an immutable-type
+            # conflict, keep the stored type but still refresh the rest.
+            effective_type = existing["type"] if type_locked else e.type
+            conn.execute(
+                """
+                INSERT INTO collections
+                    (id, project_id, type, subfolder, initial_state, visibility, name, registry_sha, updated_at)
+                VALUES (?, ?, ?, '', ?, ?, ?, ?, datetime('now'))
+                ON CONFLICT(id) DO UPDATE SET
+                    project_id = excluded.project_id,
+                    type = excluded.type,
+                    initial_state = excluded.initial_state,
+                    visibility = excluded.visibility,
+                    name = excluded.name,
+                    registry_sha = excluded.registry_sha,
+                    updated_at = datetime('now')
+                """,
+                (cid, e.id, effective_type, e.initial_state, e.visibility, e.name, registry_sha),
+            )
+        conn.execute(
+            """
+            UPDATE deployment
+               SET name = ?, tagline = ?, registry_sha = ?, updated_at = datetime('now')
+             WHERE id = 1
+            """,
+            (doc.deployment_name, doc.deployment_tagline, registry_sha),
+        )
+
+
+def _strictest_visibility(a: str, b: str) -> str:
+    """The stricter of two §22.5 visibilities on the public-exposure axis
+    (`public` < `unlisted` < `gated`). Used to enforce that a collection is set
+    only as strict or stricter than its project (S3 operator decision)."""
+    rank = {"public": 0, "unlisted": 1, "gated": 2}
+    return a if rank.get(a, 2) >= rank.get(b, 2) else b
+
+
+def _upsert_named_collection(
+    proj: ProjectEntry, subdir: str, ce: CollectionEntry, sha: str
+) -> None:
+    """Upsert one named collection (S2). Type is immutable (§22.4a): a type
+    change against an existing row is refused (logged, not applied). A None
+    manifest visibility inherits the project's visibility; a manifest that tries
+    to be *looser* than its project is clamped to the project's (S3 strictness:
+    a collection may narrow but never widen its project's visibility)."""
+    requested = ce.visibility or proj.visibility
+    visibility = _strictest_visibility(requested, proj.visibility)
+    if visibility != requested:
+        log.warning(
+            "registry: collection %s visibility %r looser than project %s %r — "
+            "clamped to %r (S3 strictness)",
+            subdir, requested, proj.id, proj.visibility, visibility,
+        )
+    with db.tx() as conn:
+        existing = conn.execute(
+            "SELECT type FROM collections WHERE id = ?", (subdir,)
+        ).fetchone()
+        if existing is not None and existing["type"] != ce.type:
+            log.error(
+                "registry: refusing immutable type change on collection %s (%s -> %s)",
+                subdir, existing["type"], ce.type,
+            )
+            return
+        conn.execute(
+            """
+            INSERT INTO collections
+                (id, project_id, type, subfolder, initial_state, visibility, name, registry_sha, updated_at)
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, datetime('now'))
+            ON CONFLICT(id) DO UPDATE SET
+                project_id = excluded.project_id,
+                initial_state = excluded.initial_state,
+                visibility = excluded.visibility,
+                name = excluded.name,
+                registry_sha = excluded.registry_sha,
+                updated_at = datetime('now')
+            """,
+            (subdir, proj.id, ce.type, subdir, ce.initial_state, visibility, ce.name, sha),
+        )
+
+
+async def _mirror_named_collections(config: Config, gitea: Gitea, doc: RegistryDoc, sha: str) -> None:
+    """§22 S2: named collections are declared by `.collection.yaml` manifests
+    inside each project's content repo (the default collection comes from
+    projects.yaml). Walk each content repo root; a subdir carrying a manifest
+    becomes a collection keyed by the subdir name. Tolerant: a transport or
+    parse failure on one project/collection logs and is skipped, never aborts
+    the wider mirror (keep last-good)."""
+    for proj in doc.projects:
+        try:
+            items = await gitea.list_dir(config.gitea_org, proj.content_repo, "", ref="main")
+        except Exception as e:  # noqa: BLE001 — GiteaError/transport: tolerate
+            log.warning("registry: cannot list %s root: %s", proj.content_repo, e)
+            continue
+        for it in items:
+            if it.get("type") != "dir":
+                continue
+            subdir = it["name"]
+            manifest = await gitea.get_contents(
+                config.gitea_org, proj.content_repo, f"{subdir}/.collection.yaml", ref="main"
+            )
+            if not manifest or manifest.get("type") != "file":
+                continue
+            mtext = base64.b64decode(manifest["content"]).decode("utf-8")
+            try:
+                ce = parse_collection_manifest(mtext)
+            except RegistryError as e:
+                log.error("registry: bad manifest %s/%s: %s", proj.content_repo, subdir, e)
+                continue
+            _upsert_named_collection(proj, subdir, ce, sha)
+
+
+async def refresh_registry(config: Config, gitea: Gitea) -> None:
+    """Mirror REGISTRY_REPO/projects.yaml into projects + deployment.
+
+    Idempotent. Raises RegistryError on a missing/invalid file and GiteaError
+    on transport failure; the caller chooses fatal-vs-tolerated.
+    """
+    item = await gitea.get_contents(
+        config.gitea_org, config.registry_repo, "projects.yaml", ref="main"
+    )
+    if not item or item.get("type") != "file":
+        raise RegistryError(
+            f"{config.gitea_org}/{config.registry_repo}/projects.yaml not found"
+        )
+    text = base64.b64decode(item["content"]).decode("utf-8")
+    # Prefer the file's last commit sha for provenance (production Gitea
+    # includes it on the contents response); fall back to the blob sha.
+    sha = item.get("last_commit_sha") or item.get("sha") or ""
+    doc = parse_registry(text)
+    from . import projects as projects_mod
+    apply_registry(doc, sha, projects_mod.resolved_default_id(config))
+    # §22 S2: discover + upsert named collections from each content repo.
+    await _mirror_named_collections(config, gitea, doc, sha)
+    log.info("registry: mirrored %d project(s) at %s", len(doc.projects), sha)

backend/app/rfc_links.py

@@ -0,0 +1,333 @@
+"""Roadmap #28 — scan submitted prose for RFC-shaped references.
+
+The scanner splits a plain-text PR description / comment body into a list
+of *segments* the frontend renders: plain-text runs interleaved with
+typed link segments. The backend never emits HTML — the frontend maps
+each segment onto a React node — so the surface is XSS-safe by
+construction and independent of any HTML-sanitization layer.
+
+Three buckets, one scan (Parts 1–3):
+
+  * ``{"type": "rfc", ...}``          — Part 1. The term matches an
+    **accepted** (``state='active'``) RFC; renders as a link to it.
+  * ``{"type": "rfc-pending", ...}``  — Part 3. The term matches a
+    **pending** RFC — a super-draft (``state='super-draft'``: accepted
+    as an idea but not yet graduated to an active RFC) — which has an
+    owner and a contribution surface. Renders as an "ask to contribute"
+    affordance carrying the owner's display name.
+  * ``{"type": "rfc-candidate", ...}`` — Part 2. The term is a
+    strong-candidate that does **not** yet have a defining RFC. Renders
+    (for a viewer with create rights) as a "create RFC for '<term>'"
+    affordance that pre-fills the propose flow.
+
+Precedence at any position is active > pending > candidate, then
+longest-match-first — an active link always wins over a contribute offer
+which always wins over a create offer for the same span.
+
+**Read-time enrichment, not submit-time persistence** (unchanged from
+Part 1): drafts are never scanned, only submitted content on the read
+paths, so links/offers track the *live* corpus. The active-RFC corpus,
+super-draft corpus, and tag taxonomy are all small and cache-resident,
+so building the index and scanning a ≤20k-char body per read is cheap.
+
+**Matching stays conservative by design.** A reference links/offers only
+when it is unlikely to be coincidental:
+
+  * ``rfc_id`` tokens (e.g. ``RFC-0001``) — inherently specific.
+  * Multi-word titles (containing whitespace, e.g. ``Open Human Model``).
+  * Hyphenated slugs (containing ``-``, e.g. ``open-human-model``).
+
+Single common-word titles/slugs are deliberately NOT matched — they
+would turn every prose occurrence into an affordance.
+
+**Part 2 candidate heuristic.** A candidate term is a **multi-word tag**
+from the #27 tag taxonomy (the de-facto set of tags the corpus already
+carries) that has no defining RFC (no active or super-draft RFC whose
+slug or title is that term). Multi-word is the same false-positive guard
+the title rule uses: a single common tag word (``identity``) would be
+far too noisy. Broader candidate detection — capitalized multi-word
+phrases mined from the text, terms repeated across recently-touched PRs,
+or the #27 Haiku (``ANTHROPIC_API_KEY``) pathway — is a sanctioned but
+deferred extension; the conservative tag-taxonomy heuristic is chosen
+here to match Part 1's false-positive-averse philosophy.
+"""
+from __future__ import annotations
+
+import json
+import re
+from typing import Any, Iterable, NamedTuple
+
+
+class Term(NamedTuple):
+    """One match key plus what to emit when it hits.
+
+    ``key`` is the lowercase span to match (word-boundary, longest-first).
+    ``kind`` is ``'active' | 'pending' | 'candidate'`` and selects the
+    emitted segment shape. ``slug``/``title`` carry the target RFC (active
+    + pending); ``owner`` is the pending RFC's owner display name;
+    ``term`` is the candidate's canonical display spelling.
+    """
+
+    key: str
+    kind: str = "active"
+    slug: str = ""
+    title: str = ""
+    owner: str = ""
+    term: str = ""
+
+
+# Lower number = higher precedence when two keys of equal length match at
+# the same position. A real link beats a contribute offer beats a create
+# offer.
+_KIND_PRIORITY = {"active": 0, "pending": 1, "candidate": 2}
+
+
+def _coerce(t: Term | tuple) -> Term:
+    """Accept the legacy ``(key, slug, title)`` 3-tuple (treated as an
+    active term) alongside :class:`Term`, so direct unit-test callers and
+    older call sites keep working."""
+    if isinstance(t, Term):
+        return t
+    key, slug, title = t  # legacy active 3-tuple
+    return Term(key=key, kind="active", slug=slug, title=title)
+
+
+def _is_word_char(c: str) -> bool:
+    """Word-boundary test. Hyphen and underscore count as word chars so a
+    match can't begin or end in the middle of a kebab/snake token."""
+    return c.isalnum() or c in ("-", "_")
+
+
+def _emit(term: Term, label: str) -> dict[str, Any]:
+    """The segment dict for a matched ``term``; ``label`` preserves source
+    casing."""
+    if term.kind == "pending":
+        return {
+            "type": "rfc-pending",
+            "slug": term.slug,
+            "label": label,
+            "title": term.title,
+            "owner": term.owner,
+        }
+    if term.kind == "candidate":
+        return {"type": "rfc-candidate", "label": label, "term": term.term}
+    return {"type": "rfc", "slug": term.slug, "label": label, "title": term.title}
+
+
+def segment_text(text: str | None, terms: Iterable[Term | tuple]) -> list[dict[str, Any]]:
+    """Split ``text`` into text / link segments against ``terms``.
+
+    ``terms`` are :class:`Term` objects (or legacy ``(key, slug, title)``
+    active 3-tuples). Matching is case-insensitive, respects word
+    boundaries on both ends, and prefers the longest key — then higher
+    :data:`_KIND_PRIORITY` — at any position.
+
+    Always returns at least one segment; for empty/None input that is a
+    single empty text segment, so callers can render uniformly.
+    """
+    ordered = sorted(
+        (_coerce(t) for t in terms),
+        key=lambda t: (-len(t.key), _KIND_PRIORITY.get(t.kind, 9)),
+    )
+    if not text:
+        return [{"type": "text", "text": text or ""}]
+
+    out: list[dict[str, Any]] = []
+    buf: list[str] = []
+    low = text.lower()
+    n = len(text)
+    i = 0
+    while i < n:
+        match: tuple[Term, int] | None = None
+        for term in ordered:
+            klen = len(term.key)
+            if klen == 0 or not low.startswith(term.key, i):
+                continue
+            before = text[i - 1] if i > 0 else ""
+            after = text[i + klen] if i + klen < n else ""
+            if _is_word_char(before) or _is_word_char(after):
+                continue
+            match = (term, klen)
+            break
+        if match is not None:
+            term, klen = match
+            if buf:
+                out.append({"type": "text", "text": "".join(buf)})
+                buf = []
+            out.append(_emit(term, text[i:i + klen]))
+            i += klen
+        else:
+            buf.append(text[i])
+            i += 1
+    if buf:
+        out.append({"type": "text", "text": "".join(buf)})
+    return out
+
+
+def _keys_for(slug: str, title: str, rfc_id: str | None) -> Iterable[str]:
+    """The match keys an RFC contributes. See the module docstring for why
+    each gate exists (conservative, false-positive-averse)."""
+    if rfc_id:
+        rid = rfc_id.strip()
+        if len(rid) >= 2:
+            yield rid.lower()
+    if title:
+        t = title.strip()
+        # Multi-word titles only — a single common word is too noisy.
+        if len(t) >= 2 and (" " in t or "\t" in t):
+            yield t.lower()
+    if slug:
+        s = slug.strip()
+        # Hyphenated slugs only — a single-token slug is a bare word.
+        if len(s) >= 2 and "-" in s:
+            yield s.lower()
+
+
+def _slugify(term: str) -> str:
+    """Deterministic kebab-case — mirrors the propose modal's slugify so a
+    tag's would-be slug compares correctly against existing RFC slugs."""
+    return re.sub(r"-+$", "", re.sub(r"^-+", "", re.sub(r"[^a-z0-9]+", "-", term.lower().strip())))
+
+
+class LinkIndex:
+    """A reusable term index built once per request and applied to many
+    bodies (a PR's description plus every comment on it)."""
+
+    def __init__(self, terms: Iterable[Term | tuple]):
+        # Coerce + order once; segment_text re-sorts defensively but a
+        # pre-sorted list keeps the per-body cost to the scan itself.
+        self._terms: list[Term] = sorted(
+            (_coerce(t) for t in terms),
+            key=lambda t: (-len(t.key), _KIND_PRIORITY.get(t.kind, 9)),
+        )
+
+    def __bool__(self) -> bool:
+        return bool(self._terms)
+
+    def segment(self, text: str | None) -> list[dict[str, Any]]:
+        return segment_text(text, self._terms)
+
+
+def _owner_display(conn, owners_json: str | None, proposed_by: str | None) -> str:
+    """The display name to show for a pending RFC's owner. First entry of
+    ``owners_json`` resolved to its user row's display name, falling back
+    to the bare login, then ``proposed_by``, then a neutral noun."""
+    login = None
+    try:
+        owners = json.loads(owners_json or "[]")
+        if isinstance(owners, list):
+            login = next((o for o in owners if isinstance(o, str) and o.strip()), None)
+    except (ValueError, TypeError):
+        login = None
+    if login:
+        row = conn.execute(
+            "SELECT display_name FROM users WHERE gitea_login = ?", (login,)
+        ).fetchone()
+        if row and row["display_name"]:
+            return row["display_name"]
+        return login
+    return (proposed_by or "").strip() or "the proposer"
+
+
+def _tag_universe(conn) -> list[str]:
+    """Distinct tags across the cached corpus (the #27 de-facto taxonomy),
+    preserving original spelling; case-deduped."""
+    rows = conn.execute("SELECT tags_json FROM cached_rfcs").fetchall()
+    out: list[str] = []
+    seen: set[str] = set()
+    for r in rows:
+        try:
+            tags = json.loads(r["tags_json"] or "[]")
+        except (ValueError, TypeError):
+            continue
+        if not isinstance(tags, list):
+            continue
+        for t in tags:
+            if not isinstance(t, str):
+                continue
+            tag = t.strip()
+            low = tag.lower()
+            if tag and low not in seen:
+                seen.add(low)
+                out.append(tag)
+    return out
+
+
+def build_index(
+    conn,
+    *,
+    exclude_slug: str | None = None,
+    include_pending: bool = True,
+    include_candidates: bool = True,
+) -> LinkIndex:
+    """Build a :class:`LinkIndex` over the three buckets.
+
+    ``exclude_slug`` drops the RFC the surrounding surface is itself scoped
+    to, so an RFC's own title/id/slug don't self-link (or self-offer)
+    inside its own PR or discussion. Precedence is enforced by insertion
+    order — active keys are added first and a later bucket never overrides
+    an already-claimed key.
+    """
+    terms: list[Term] = []
+    seen: set[str] = set()
+
+    def add(key: str, term: Term) -> None:
+        if key in seen:
+            return
+        seen.add(key)
+        terms.append(term)
+
+    # --- Part 1: accepted (active) RFCs. ORDER BY slug makes key
+    # de-duplication deterministic when two RFCs would contribute the
+    # same key (first slug wins). ---
+    active_rows = conn.execute(
+        "SELECT slug, title, rfc_id FROM cached_rfcs WHERE state = 'active' ORDER BY slug"
+    ).fetchall()
+    # Track every slug + title that *has* a defining RFC, so Part 2 never
+    # offers to create one that already exists (active or pending).
+    defined_slugs: set[str] = set()
+    defined_titles: set[str] = set()
+    for r in active_rows:
+        slug = r["slug"]
+        defined_slugs.add((slug or "").lower())
+        defined_titles.add((r["title"] or "").strip().lower())
+        if exclude_slug is not None and slug == exclude_slug:
+            continue
+        title = r["title"] or ""
+        rfc_id = r["rfc_id"] if "rfc_id" in r.keys() else None
+        for key in _keys_for(slug, title, rfc_id):
+            add(key, Term(key=key, kind="active", slug=slug, title=title))
+
+    # --- Part 3: pending (super-draft) RFCs. ---
+    pending_rows = conn.execute(
+        """
+        SELECT slug, title, rfc_id, owners_json, proposed_by
+          FROM cached_rfcs WHERE state = 'super-draft' ORDER BY slug
+        """
+    ).fetchall()
+    for r in pending_rows:
+        slug = r["slug"]
+        defined_slugs.add((slug or "").lower())
+        defined_titles.add((r["title"] or "").strip().lower())
+        if not include_pending:
+            continue
+        if exclude_slug is not None and slug == exclude_slug:
+            continue
+        title = r["title"] or ""
+        rfc_id = r["rfc_id"] if "rfc_id" in r.keys() else None
+        owner = _owner_display(conn, r["owners_json"], r["proposed_by"])
+        for key in _keys_for(slug, title, rfc_id):
+            add(key, Term(key=key, kind="pending", slug=slug, title=title, owner=owner))
+
+    # --- Part 2: strong-candidate terms with no defining RFC. ---
+    if include_candidates:
+        for tag in _tag_universe(conn):
+            low = tag.lower()
+            # Conservative: multi-word tags only (same guard as titles).
+            if " " not in tag and "\t" not in tag:
+                continue
+            if low in defined_titles or low in defined_slugs or _slugify(tag) in defined_slugs:
+                continue
+            add(low, Term(key=low, kind="candidate", term=tag))
+
+    return LinkIndex(terms)

backend/app/tag_suggest.py

@@ -0,0 +1,244 @@
+"""Roadmap #27 — Claude Haiku tag suggestions for the propose-RFC modal.
+
+A cheap, fast assist: given the partial RFC draft a user is typing, ask
+Claude Haiku to recommend tags drawn ONLY from the tags already in use
+across the corpus. v1 has no curated tag list — tags are free-form chip
+input (§9.1) — so "the taxonomy" is the de-facto set of distinct tags
+the existing RFCs already carry. The model is constrained to that set
+and MUST NOT invent new tags; taxonomy extension (letting the model
+propose genuinely new tags) is a deferred follow-up per the roadmap.
+
+Why Haiku specifically: cost. Picking a few reasonable tags from a known
+set is well within Haiku's range, and the modal fires this repeatedly as
+the user types, so the per-call price has to stay small.
+
+The whole surface degrades to silence rather than error: no Anthropic
+key, no provider, an empty corpus, a rate-limited caller, an empty
+draft, or an unparseable model reply all yield an empty suggestion list.
+The propose modal hides its suggestion row on an empty list, so the
+fallback is simply the existing free-form chip input with nothing extra
+shown.
+"""
+from __future__ import annotations
+
+import json
+import logging
+import os
+import time
+from dataclasses import dataclass
+
+from . import db
+from .providers import BaseProvider, construct_haiku
+
+log = logging.getLogger(__name__)
+
+# Bound the universe handed to the model so a large corpus can't blow up
+# the prompt size (and the cost). The most-common tags matter most.
+_UNIVERSE_CAP = 200
+
+# How many suggestions we ever return to the modal.
+DEFAULT_MAX_SUGGESTIONS = 6
+
+
+@dataclass
+class Draft:
+    """The partial propose-RFC draft. `pitch` is the "why is this needed"
+    rationale; `use_case` is the #26 optional ground-truth field."""
+
+    title: str = ""
+    pitch: str = ""
+    use_case: str = ""
+
+    def is_empty(self) -> bool:
+        return not (self.title.strip() or self.pitch.strip() or self.use_case.strip())
+
+
+def haiku_provider(config) -> BaseProvider | None:
+    """Construct a dedicated Claude Haiku provider from the operator's
+    Anthropic key, or return None when no key is configured.
+
+    None means "suggestions unavailable" — the caller returns an empty
+    list and the modal shows nothing. This is the seam tests monkeypatch
+    to inject a fake provider without a real key. There is no RFC slug at
+    propose time, so the §6.7 per-RFC funder path deliberately does not
+    apply: tag suggestion always runs on the operator's own key.
+    """
+    key = getattr(config, "anthropic_api_key", "") or ""
+    if not key:
+        return None
+    return construct_haiku(key)
+
+
+def gather_tag_universe(cap: int = _UNIVERSE_CAP) -> list[str]:
+    """Every distinct tag in use across the cached corpus, most-common
+    first (ties broken alphabetically for determinism), capped.
+
+    This is the universe the model is constrained to. An empty corpus
+    yields an empty list, which short-circuits suggestion to silence.
+    """
+    rows = db.conn().execute("SELECT tags_json FROM cached_rfcs").fetchall()
+    counts: dict[str, int] = {}
+    for r in rows:
+        try:
+            tags = json.loads(r["tags_json"] or "[]")
+        except (ValueError, TypeError):
+            continue
+        if not isinstance(tags, list):
+            continue
+        for t in tags:
+            if not isinstance(t, str):
+                continue
+            tag = t.strip()
+            if tag:
+                counts[tag] = counts.get(tag, 0) + 1
+    ranked = sorted(counts, key=lambda t: (-counts[t], t.lower()))
+    return ranked[:cap]
+
+
+# ---------------------------------------------------------------------------
+# Rate limiting — in-process, per-user sliding window.
+#
+# Cost control, not security: the `require_contributor` gate already
+# bounds callers to authenticated beta users, and the modal debounces.
+# This is the backstop against a stuck/abusive client hammering the
+# endpoint. In-memory is sufficient (single-process uvicorn on the VM)
+# and resets on restart, which is fine for a cost guard.
+# ---------------------------------------------------------------------------
+
+_CALLS: dict[int, list[float]] = {}
+
+
+def _rate_config() -> tuple[int, float]:
+    try:
+        max_calls = int(os.environ.get("TAG_SUGGEST_RATE_MAX", "30"))
+    except ValueError:
+        max_calls = 30
+    try:
+        window = float(os.environ.get("TAG_SUGGEST_RATE_WINDOW_SECONDS", "60"))
+    except ValueError:
+        window = 60.0
+    return max_calls, window
+
+
+def rate_limit_ok(user_id: int, *, now: float | None = None) -> bool:
+    """True if this call is within the per-user window; records the call.
+    `now` is injectable for tests (defaults to a monotonic clock)."""
+    max_calls, window = _rate_config()
+    t = time.monotonic() if now is None else now
+    calls = _CALLS.setdefault(user_id, [])
+    cutoff = t - window
+    calls[:] = [c for c in calls if c > cutoff]
+    if len(calls) >= max_calls:
+        return False
+    calls.append(t)
+    return True
+
+
+def reset_rate_limits() -> None:
+    """Test seam — clear the in-process window state."""
+    _CALLS.clear()
+
+
+# ---------------------------------------------------------------------------
+# Prompt + parse.
+# ---------------------------------------------------------------------------
+
+_SYSTEM = (
+    "You suggest topic tags for a draft RFC — a structured proposal "
+    "document in a collection. You are given the draft's title, its "
+    "rationale, an optional use case, and the exact set of tags already "
+    "in use across the collection. Choose the tags from that set that "
+    "best fit the draft.\n"
+    "Rules:\n"
+    "- Choose ONLY from the provided tag set. Never invent a tag.\n"
+    "- Order best-fit first. Omit weak fits rather than padding the list.\n"
+    "- Return at most {max} tags.\n"
+    "Respond with ONLY a JSON array, no prose, of the form:\n"
+    '[{{"tag": "<exact tag from the set>", "confidence": <number between 0 and 1>}}]\n'
+    "If no tag in the set fits the draft, return []."
+)
+
+
+def _build_messages(draft: Draft, universe: list[str], max_suggestions: int):
+    system = _SYSTEM.format(max=max_suggestions)
+    parts: list[str] = []
+    if draft.title.strip():
+        parts.append(f"Title: {draft.title.strip()[:300]}")
+    if draft.pitch.strip():
+        parts.append(f"Why this RFC is needed:\n{draft.pitch.strip()[:4000]}")
+    if draft.use_case.strip():
+        parts.append(f"What it will be used for:\n{draft.use_case.strip()[:4000]}")
+    parts.append(
+        "Tags already in use (choose only from these):\n" + ", ".join(universe)
+    )
+    return system, [{"role": "user", "content": "\n\n".join(parts)}]
+
+
+def _extract_json_array(text: str):
+    start = text.find("[")
+    end = text.rfind("]")
+    if start == -1 or end == -1 or end < start:
+        return None
+    try:
+        return json.loads(text[start : end + 1])
+    except ValueError:
+        return None
+
+
+def parse_reply(text: str, universe: list[str], max_suggestions: int) -> list[dict]:
+    """Parse the model reply into a clean, universe-constrained list.
+
+    Tolerant of the model returning bare strings or objects, extra prose
+    around the JSON, unknown/invented tags (dropped), duplicate tags
+    (deduped), and missing/garbage confidences (defaulted + clamped).
+    """
+    data = _extract_json_array(text or "")
+    if not isinstance(data, list):
+        return []
+    # Map back to the canonical spelling in the universe, case-insensitively,
+    # so a model that lowercases a tag still resolves to the real one.
+    canonical = {t.lower(): t for t in universe}
+    out: list[dict] = []
+    seen: set[str] = set()
+    for item in data:
+        if isinstance(item, dict):
+            raw = item.get("tag")
+            conf = item.get("confidence")
+        elif isinstance(item, str):
+            raw, conf = item, None
+        else:
+            continue
+        if not isinstance(raw, str):
+            continue
+        tag = canonical.get(raw.strip().lower())
+        if tag is None or tag in seen:
+            continue
+        try:
+            c = float(conf) if conf is not None else 0.5
+        except (ValueError, TypeError):
+            c = 0.5
+        c = max(0.0, min(1.0, c))
+        out.append({"tag": tag, "confidence": round(c, 3)})
+        seen.add(tag)
+        if len(out) >= max_suggestions:
+            break
+    return out
+
+
+def suggest(
+    provider: BaseProvider,
+    draft: Draft,
+    universe: list[str],
+    max_suggestions: int = DEFAULT_MAX_SUGGESTIONS,
+) -> list[dict]:
+    """Orchestrate one suggestion call. Returns [] for an empty draft or
+    empty universe (no model call), and for any provider/parse failure."""
+    if draft.is_empty() or not universe:
+        return []
+    system, history = _build_messages(draft, universe, max_suggestions)
+    try:
+        text = provider.send(system, history)
+    except Exception as exc:  # provider/network failure → silent empty
+        log.warning("tag-suggest provider failed: %s", exc)
+        return []
+    return parse_reply(text, universe, max_suggestions)

backend/app/turnstile.py

@@ -0,0 +1,166 @@
+"""§6.2 / v0.12.0 / roadmap item #10: CloudFlare Turnstile siteverify.
+
+The OTC request endpoint (`/auth/otc/request`) is the abuse hot path
+of the auth surface since v0.7.0 — the per-email cooldown stops the
+trivial back-to-back loop, but it does not stop a distributed scraper
+that fans out across a large invitee list to harvest the "this email
+is admitted vs. this email is not" signal indirectly (timing
+differences, SMTP bounce-rate observation). v0.12.0 gates the request
+endpoint behind a one-step browser-side Turnstile challenge before the
+bcrypt hash + SMTP send.
+
+Stateless: no DB writes, no schema change. The siteverify call to
+CloudFlare lives entirely in this module; the endpoint handler in
+`main.py` thin-wraps `verify_token`.
+
+Tunables (read at call time so tests can monkeypatch):
+
+  * `CLOUDFLARE_TURNSTILE_SECRET`  — the operator-provisioned secret
+    key from the Turnstile dashboard. Lives in GCP Secret Manager in
+    production; absent in tests (which monkeypatch the siteverify
+    transport). When unset, the behavior depends on `TURNSTILE_REQUIRED`:
+      - `TURNSTILE_REQUIRED=true`  → fail closed (`misconfigured`).
+      - `TURNSTILE_REQUIRED=false` (default) → skip verification entirely
+        and admit the request. This is the dev/test path and the
+        "operator hasn't wired the secret yet" path; production
+        deployments **should** set `TURNSTILE_REQUIRED=true` once the
+        secret is in place so a regression in the secret wiring fails
+        loudly instead of silently disabling abuse defense.
+
+  * `TURNSTILE_REQUIRED`           — `true` / `false` (default `false`).
+    When `false` and the secret is absent, the gate is open. When
+    `true` and the secret is absent, the endpoint refuses with a
+    misconfigured-auth shape rather than silently letting requests
+    through.
+
+  * `TURNSTILE_SITEVERIFY_URL`     — points at the real CloudFlare
+    endpoint by default. Override in tests to redirect at a mock
+    URL when `httpx.MockTransport` isn't ergonomic for the case.
+
+The siteverify contract is documented at
+https://developers.cloudflare.com/turnstile/get-started/server-side-validation/.
+We POST `secret` + `response` (and optionally `remoteip`) as form
+fields and read back `{"success": true|false, ...}`. Any network /
+parse failure on the siteverify call is treated as a verification
+failure (`network`) — the abuse path is to skip the challenge, so
+"can't reach CloudFlare" defaults to "refuse the request" when
+`TURNSTILE_REQUIRED=true`, and "admit" when `TURNSTILE_REQUIRED=false`.
+"""
+from __future__ import annotations
+
+import logging
+import os
+from dataclasses import dataclass
+
+import httpx
+
+log = logging.getLogger(__name__)
+
+
+SITEVERIFY_URL = "https://challenges.cloudflare.com/turnstile/v0/siteverify"
+
+
+def _secret() -> str:
+    return os.environ.get("CLOUDFLARE_TURNSTILE_SECRET", "").strip()
+
+
+def _required() -> bool:
+    raw = os.environ.get("TURNSTILE_REQUIRED", "").strip().lower()
+    return raw in ("1", "true", "yes", "on")
+
+
+def _siteverify_url() -> str:
+    return os.environ.get("TURNSTILE_SITEVERIFY_URL", "").strip() or SITEVERIFY_URL
+
+
+async def _siteverify_post(url: str, data: dict) -> httpx.Response:
+    """Perform the siteverify POST on an `httpx.AsyncClient`.
+
+    Isolated as a narrow seam (I4, security-audit-0026): the call is
+    awaited so a slow CloudFlare response can't block the event loop,
+    and tests patch *this function* rather than the shared
+    `httpx.AsyncClient` (which other modules — gitea, docs — also
+    construct, so a global patch would break app boot).
+    """
+    async with httpx.AsyncClient(timeout=10.0) as client:
+        return await client.post(url, data=data)
+
+
+@dataclass
+class VerifyOutcome:
+    """Result of a Turnstile siteverify call.
+
+    `ok`: the request **may proceed**. True both for "siteverify said
+    success" and for "no secret configured AND not required" (the
+    dev/test soft-fail path).
+
+    `reason`: one of
+      * 'ok'             — siteverify returned success.
+      * 'skipped'        — no secret configured, TURNSTILE_REQUIRED=false.
+                            The gate is open; the endpoint admits the request.
+      * 'misconfigured'  — TURNSTILE_REQUIRED=true but no secret in env.
+                            The endpoint fails closed with 500.
+      * 'missing-token'  — the client did not send a token at all and
+                            verification is required.
+      * 'failed'         — siteverify returned success=false. The
+                            endpoint refuses with 400.
+      * 'network'        — siteverify call raised. Treated as a failure
+                            under TURNSTILE_REQUIRED=true.
+    """
+    ok: bool
+    reason: str
+
+
+async def verify_token(token: str | None, *, client_ip: str | None = None) -> VerifyOutcome:
+    """Validate a Turnstile token against CloudFlare's siteverify endpoint.
+
+    Returns a VerifyOutcome describing whether the calling endpoint
+    should proceed. The endpoint maps `ok=False` to an HTTP status per
+    the `reason`:
+
+      * 'misconfigured' → 500 "auth misconfigured"
+      * 'missing-token' / 'failed' / 'network' → 400 "verification failed"
+
+    Async (I4, security-audit-0026): the siteverify call is awaited on an
+    `httpx.AsyncClient` so a slow CloudFlare response can't block the
+    event loop (the prior synchronous `httpx.post` stalled the single
+    worker for up to the 10s timeout). Callers must `await` it.
+
+    Tests monkeypatch `_siteverify_post` (the narrow async seam) to avoid
+    touching the real CloudFlare endpoint and to keep the patch off the
+    shared `httpx.AsyncClient`. No real keys are ever embedded in tests.
+    """
+    secret = _secret()
+    required = _required()
+
+    if not secret:
+        if required:
+            log.warning("Turnstile required but CLOUDFLARE_TURNSTILE_SECRET is unset; failing closed")
+            return VerifyOutcome(ok=False, reason="misconfigured")
+        # Dev/test/soft-fail path: no secret, not required → gate is open.
+        return VerifyOutcome(ok=True, reason="skipped")
+
+    if not token or not token.strip():
+        # Secret is set, so verification is in force. A missing token
+        # is a hard refuse — the frontend should have rendered the
+        # widget and collected one.
+        return VerifyOutcome(ok=False, reason="missing-token")
+
+    data = {"secret": secret, "response": token.strip()}
+    if client_ip:
+        data["remoteip"] = client_ip
+
+    try:
+        response = await _siteverify_post(_siteverify_url(), data)
+        payload = response.json()
+    except Exception as exc:  # network, JSON parse, etc.
+        log.warning("Turnstile siteverify call failed: %s", exc)
+        return VerifyOutcome(ok=False, reason="network")
+
+    if payload.get("success") is True:
+        return VerifyOutcome(ok=True, reason="ok")
+
+    # `error-codes` is a list of strings on failure; we log the codes
+    # for the operator without surfacing them to the client.
+    log.info("Turnstile siteverify rejected token: %s", payload.get("error-codes"))
+    return VerifyOutcome(ok=False, reason="failed")

backend/app/webhooks.py

@@ -12,10 +12,11 @@ import hashlib
 import hmac
 import json
 import logging
+import os
 
 from fastapi import APIRouter, Header, HTTPException, Request
 
-from . import cache, db
+from . import cache, db, projects as projects_mod, registry as registry_mod
 from .config import Config
 from .gitea import Gitea
 
@@ -40,7 +41,27 @@ def make_router(config: Config, gitea: Gitea) -> APIRouter:
         x_gitea_signature: str = Header(default=""),
     ):
         body = await request.body()
-        if config.webhook_secret:
+        # v0.18.0: defense in depth. config.py refuses to start
+        # when the secret is empty unless `RFC_APP_INSECURE_WEBHOOKS=1`
+        # is set; this branch catches the dev-bypass case (the only
+        # path where `config.webhook_secret` can be empty) and surfaces
+        # it loudly to the client. A POST that lands here with an
+        # empty secret on a production deployment indicates a
+        # mis-configuration (somebody flipped the bypass in prod),
+        # and the loud 500 is the proposal's whole point.
+        insecure = os.environ.get("RFC_APP_INSECURE_WEBHOOKS", "").strip() == "1"
+        if not config.webhook_secret:
+            if not insecure:
+                log.error(
+                    "webhook receiver misconfigured: GITEA_WEBHOOK_SECRET is empty "
+                    "and RFC_APP_INSECURE_WEBHOOKS=1 is not set"
+                )
+                raise HTTPException(status_code=500, detail="Webhook receiver misconfigured")
+            log.warning(
+                "webhook receiver running with RFC_APP_INSECURE_WEBHOOKS=1 — "
+                "signature verification is DISABLED. Production deployments MUST NOT set this."
+            )
+        else:
             if not _verify_signature(body, x_gitea_signature, config.webhook_secret):
                 raise HTTPException(status_code=401, detail="Invalid signature")
 
@@ -58,9 +79,22 @@ def make_router(config: Config, gitea: Gitea) -> APIRouter:
         except Exception:
             payload = {}
         repo_full = (payload.get("repository") or {}).get("full_name") or ""
-        meta_full = f"{config.gitea_org}/{config.meta_repo}"
+        registry_full = f"{config.gitea_org}/{config.registry_repo}"
+        content_repo = projects_mod.default_content_repo(config)
+        if not content_repo:
+            log.warning("webhook: default project content_repo is unknown; corpus refresh skipped")
+        content_full = f"{config.gitea_org}/{content_repo}" if content_repo else None
         try:
-            if repo_full == meta_full or not repo_full:
+            if repo_full == registry_full:
+                # §22.2: a registry-repo push re-mirrors the projects table.
+                # Tolerate a malformed projects.yaml (keep last-good rows); let a
+                # transport error bubble to the outer 500 so an unreachable Gitea
+                # on a registry push is loud rather than silently dropped.
+                try:
+                    await registry_mod.refresh_registry(config, gitea)
+                except registry_mod.RegistryError:
+                    log.exception("registry webhook: invalid projects.yaml; keeping last-good")
+            elif content_full and (repo_full == content_full or not repo_full):
                 await cache.refresh_meta_repo(config, gitea)
                 await cache.refresh_meta_branches(config, gitea)
                 await cache.refresh_meta_pulls(config, gitea)
@@ -68,6 +102,12 @@ def make_router(config: Config, gitea: Gitea) -> APIRouter:
                 slug = _slug_for_repo(repo_full)
                 if slug:
                     await cache.refresh_rfc_repo(config, gitea, slug)
+                else:
+                    log.info(
+                        "webhook received for unknown repo: repo_full=%s event=%s "
+                        "(no cached_rfcs row matched; hook may be on a fork or stale)",
+                        repo_full, event,
+                    )
         except Exception:
             log.exception("webhook refresh failed")
             raise HTTPException(status_code=500, detail="Refresh failed")

backend/migrations/017_device_trust.sql

@@ -0,0 +1,75 @@
+-- §6.2 / v0.11.0: trust device for 30 days (roadmap item #9).
+--
+-- After a successful OTC or passcode sign-in, the user can check
+-- "trust this device for 30 days." The framework then issues a
+-- server-issued opaque device-trust token, stores its hash on this
+-- table, and sets a long-lived HttpOnly + Secure + SameSite=Lax
+-- cookie carrying the raw token. On a subsequent visit, the cookie is
+-- presented at `/auth/device-trust/start`; if the server can match the
+-- hash to a non-expired non-revoked row, the user is signed in without
+-- another OTC / passcode round-trip.
+--
+-- v0.11.0 introduces no new env vars. The 30-day window is hard-coded
+-- in `backend/app/device_trust.py`; raising or lowering it (or making
+-- it user-selectable) is a §19.2 candidate, alongside the cross-device
+-- session-revocation surface this table will eventually share with the
+-- v0.10.0 passcode-lockout shape (see SPEC §19.2 / SESSIONS-AND-DEVICES).
+--
+-- Storage shape:
+--
+--   * `id` — surrogate key. Lets the revoke-device UI address a single
+--     row by id without leaking the token shape.
+--   * `user_id` — FK into users(id) with cascade on delete. A deleted
+--     user automatically loses every trusted device.
+--   * `device_token_hash` — bcrypt hash of the random opaque token
+--     issued at trust-time. The raw token only ever lives in the
+--     outbound `Set-Cookie` header and the inbound `Cookie` header;
+--     server-side storage is the hash, so a DB compromise does not
+--     hand attackers a stash of valid device tokens.
+--   * `created_at` — when the row was issued.
+--   * `expires_at` — `created_at + 30 days`. A row past this timestamp
+--     is dead; the lookup path refuses it without further checks.
+--   * `user_agent` — the User-Agent header captured at issuance.
+--     Stored verbatim (truncated to 1024 chars at the application
+--     layer) so the revoke-device UI can show a rough device label.
+--     Not used for any auth decision — purely a hint to the user
+--     reviewing their device list.
+--   * `last_seen_at` — refreshed every time the row authenticates a
+--     request. Lets the revoke-device UI surface "last used 3 days
+--     ago" so the user can tell which row corresponds to which
+--     device.
+--   * `revoked_at` — NULL means active; non-NULL stamps when the user
+--     (or admin) revoked the row. Lookups treat any non-NULL value
+--     as "this row is dead" without consulting the expiry; the
+--     revoke gesture is intentionally one-way (a revoked device must
+--     re-trust to come back online).
+--
+-- Indexing: a unique index on `device_token_hash` so collisions are
+-- detectable at insert time (the token space is 256 bits of CSPRNG
+-- entropy, so a collision is structurally impossible, but the
+-- declaration documents the invariant). A separate index on
+-- `(user_id, revoked_at)` so the revoke-device UI's list query is
+-- a covering walk.
+--
+-- The bcrypt dependency reused here was added in v0.7.0 for OTC and
+-- extended in v0.10.0 for passcodes; v0.11.0 needs no new dep.
+--
+-- The cookie shape: `rfc_device_trust` carries the raw token,
+-- HttpOnly, Secure, SameSite=Lax, Max-Age=2592000 (30 days). It is
+-- "essential" per the v0.13.0 cookie-consent banner (it is part of
+-- authentication, not analytics), so it is set regardless of the
+-- user's analytics / other-cookies choices.
+
+CREATE TABLE device_trust (
+    id                  INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id             INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    device_token_hash   TEXT NOT NULL,
+    created_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    expires_at          TEXT NOT NULL,
+    user_agent          TEXT NOT NULL DEFAULT '',
+    last_seen_at        TEXT NOT NULL DEFAULT (datetime('now')),
+    revoked_at          TEXT
+);
+
+CREATE UNIQUE INDEX idx_device_trust_token_hash ON device_trust (device_token_hash);
+CREATE INDEX idx_device_trust_user ON device_trust (user_id, revoked_at);

backend/migrations/018_rfc_invitations.sql

@@ -0,0 +1,177 @@
+-- §6 / §10 / v0.16.0: owner-only invite for per-RFC contribution +
+-- discussion (roadmap item #12).
+--
+-- Distinct from a platform-level grant (`users.permission_state`,
+-- v0.8.0 / item #6). This row is per-RFC membership: the RFC's owner
+-- invites a specific email to either open PRs against that RFC
+-- (`role_in_rfc='contributor'`) or to participate in the RFC's PR-less
+-- discussion only (`role_in_rfc='discussant'`). Non-invited users keep
+-- the v0.6.0 anonymous-read contract — they can read but cannot
+-- write/discuss that specific RFC.
+--
+-- Coordinates with item #16's parallel work this wave: that item
+-- adds platform-wide invitation tokens; this one adds per-RFC
+-- collaboration rows. To avoid table-name + concept collisions the
+-- two surfaces are scoped distinctly — this migration owns slot 018
+-- and names everything `rfc_*` (RFC-scoped); #16 will use a later
+-- slot and name its tables under a different prefix (`invite_tokens`
+-- or similar) at the user/platform level.
+--
+-- Tables in this migration:
+--
+--   * `rfc_invitations` — one row per (rfc, invitee_email) invite
+--     issued by the RFC's owner. Carries the role-in-RFC the
+--     invitation grants, the opaque token the email link encodes,
+--     the lifecycle state, and the audit trail (who invited, when
+--     accepted, by which user_id if any).
+--
+--   * `rfc_collaborators` — one row per (rfc, user_id, role_in_rfc)
+--     after an invitation is accepted. This is the table the
+--     write-gate consults: "is the viewer named here for this RFC?"
+--     Separating the two means the invitation row carries the
+--     issue/accept lifecycle while the collaborator row is the
+--     compact membership-check substrate. A grant via collaborator
+--     can exist independently of a live invitation (admin-only
+--     direct insert is a §19.2 candidate; v0.16.0 only writes
+--     collaborator rows via the accept path).
+--
+-- Authorization model the application layer enforces on top of these
+-- rows (not encoded in SQL — the schema is just storage):
+--
+--   * Writes (open PR, post discussion message, open discussion
+--     thread) to an RFC require ONE of:
+--       (a) the viewer is named in this RFC's `rfc_collaborators`
+--           with the appropriate role_in_rfc, OR
+--       (b) the viewer holds a globally privileged role (admin,
+--           owner of the platform) per the existing §6 helpers, OR
+--       (c) the viewer is named in the RFC's frontmatter owners
+--           list (the §6 RFC-owner concept, which already grants
+--           the maximal per-RFC capability).
+--
+--   * Reads remain on the v0.6.0 anonymous-read contract — anyone
+--     can read any non-withdrawn RFC. Item #12 does not narrow this.
+--
+--   * Only the RFC's owner (per `cached_rfcs.owners_json`) can
+--     invite. App admins/owners also can (they have the maximal
+--     per-RFC capability by construction).
+--
+-- Storage shape — `rfc_invitations`:
+--
+--   * `id` — surrogate key; the revoke-by-id surface addresses a
+--     single row without leaking the token shape.
+--
+--   * `rfc_slug` — TEXT NOT NULL; the RFC the invitation scopes to.
+--     We FK against `cached_rfcs(slug)` so a withdrawn/deleted RFC
+--     cascades its invitations away cleanly. The §4 cache contract
+--     says cached_rfcs is rebuildable from Gitea; per the same
+--     contract, invitations are app-truth (no Git substrate), so
+--     the cascade is the right direction.
+--
+--   * `inviter_user_id` — the owner who issued the invite. ON
+--     DELETE SET NULL because losing the inviter's user row should
+--     not cascade-delete invitations they sent (the row stays as
+--     audit; the UI renders "by (deleted user)" the same way the
+--     audit log does for orphaned actors).
+--
+--   * `invitee_email` — TEXT NOT NULL; the email the invitation
+--     was sent to. Stored verbatim (case-preserved) so the email
+--     body can address the invitee in their original shape; the
+--     accept path matches case-insensitively.
+--
+--   * `role_in_rfc` — CHECK in {'contributor' | 'discussant'}.
+--     `contributor` lets the user open PRs against the RFC AND
+--     post in its discussion (PR-permission strictly includes
+--     discussion-permission); `discussant` only lets them post
+--     in discussion. Future roles (e.g., 'arbiter') would be
+--     additions; v0.16.0 ships the two.
+--
+--   * `status` — CHECK in {'pending' | 'accepted' | 'revoked' |
+--     'expired'}. Default 'pending'. `accepted` flips on the
+--     accept endpoint; `revoked` on the owner's revoke gesture;
+--     `expired` lazily on read (the accept endpoint refuses a
+--     row whose expires_at has passed, regardless of the column
+--     value).
+--
+--   * `token` — opaque high-entropy string the email link
+--     encodes. Stored verbatim (not hashed) because the
+--     invitation token is single-use and lower-stakes than a
+--     session token: it grants per-RFC role only, and is bounded
+--     by expires_at. Hashing the token here is a §19.2 candidate
+--     if/when the threat model demands it. UNIQUE so the accept
+--     path is a single-row lookup.
+--
+--   * `expires_at` — TEXT timestamp. Set to `created_at + 30 days`
+--     at insert time by the application layer. Accept refuses past
+--     this point; the row can still be revoked or re-issued.
+--
+--   * `created_at` — when the invitation was issued.
+--
+--   * `accepted_at` — when the invitee accepted (NULL until then).
+--
+--   * `accepted_by_user_id` — the user row that accepted. NULL
+--     until acceptance. On a fresh email (no platform user yet)
+--     the accept endpoint requires the invitee to sign in first
+--     via the v0.7.0 OTC path; that path provisions the user row,
+--     after which the accept call lands the user_id here.
+--
+-- Indexing:
+--
+--   * UNIQUE on `token` so the accept lookup is a primary-key-shape
+--     hit and accidental collisions are detectable at insert time.
+--   * (rfc_slug, status) for the owner's "list pending/accepted for
+--     this RFC" surface — the most frequent query.
+--   * (invitee_email, status) for a future cross-RFC "show me my
+--     pending invites" inbox; v0.16.0 doesn't ship that surface but
+--     the index slot is cheap and aligned with the data shape.
+--
+-- Storage shape — `rfc_collaborators`:
+--
+--   * `id` — surrogate key.
+--   * `rfc_slug` — TEXT NOT NULL FK cached_rfcs(slug) ON DELETE CASCADE.
+--   * `user_id` — INTEGER NOT NULL FK users(id) ON DELETE CASCADE.
+--     A deleted user loses every per-RFC role automatically (mirrors
+--     the device_trust / passcode cascade shape).
+--   * `role_in_rfc` — same CHECK as the invitation table.
+--   * `invitation_id` — INTEGER FK rfc_invitations(id) ON DELETE
+--     SET NULL. Audit pointer to the row that minted this
+--     collaborator; NULL is allowed so a future admin-direct grant
+--     path (a §19.2 candidate) can mint a collaborator with no
+--     originating invitation. v0.16.0 always populates this.
+--   * `created_at` — when the collaborator row was minted.
+--
+-- Indexing on collaborators:
+--   * UNIQUE on (rfc_slug, user_id) — a single user can hold at most
+--     one role per RFC. Re-accepting an invitation upgrades the row
+--     (discussant → contributor) but never duplicates.
+--   * (user_id) for "what RFCs am I a collaborator on?" reads.
+
+CREATE TABLE rfc_invitations (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug                TEXT NOT NULL REFERENCES cached_rfcs(slug) ON DELETE CASCADE,
+    inviter_user_id         INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    invitee_email           TEXT NOT NULL,
+    role_in_rfc             TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    status                  TEXT NOT NULL DEFAULT 'pending'
+        CHECK (status IN ('pending', 'accepted', 'revoked', 'expired')),
+    token                   TEXT NOT NULL,
+    expires_at              TEXT NOT NULL,
+    created_at              TEXT NOT NULL DEFAULT (datetime('now')),
+    accepted_at             TEXT,
+    accepted_by_user_id     INTEGER REFERENCES users(id) ON DELETE SET NULL
+);
+
+CREATE UNIQUE INDEX idx_rfc_invitations_token ON rfc_invitations (token);
+CREATE INDEX idx_rfc_invitations_rfc_status ON rfc_invitations (rfc_slug, status);
+CREATE INDEX idx_rfc_invitations_email_status ON rfc_invitations (invitee_email, status);
+
+CREATE TABLE rfc_collaborators (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL REFERENCES cached_rfcs(slug) ON DELETE CASCADE,
+    user_id         INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role_in_rfc     TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    invitation_id   INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now'))
+);
+
+CREATE UNIQUE INDEX idx_rfc_collaborators_unique ON rfc_collaborators (rfc_slug, user_id);
+CREATE INDEX idx_rfc_collaborators_user ON rfc_collaborators (user_id);

backend/migrations/019_user_invite_tokens.sql

@@ -0,0 +1,105 @@
+-- §6.1 / v0.17.0: admin-create user with role + invite email (roadmap item #16).
+--
+-- Distinguishes from the v0.8.0 / v0.9.0 self-serve beta-access shape:
+-- here an *admin* creates a `users` row *before* the invited person has
+-- ever signed in, assigns them a role at creation time, and sends them
+-- an invite email carrying a claim link. The invitee clicks the link,
+-- the claim flow consumes the token (which is itself proof of email
+-- control), the row is marked claimed, and the user is signed in
+-- inheriting the pre-set role.
+--
+-- Migration slot 019 is allocated to this release. Slot 018 is reserved
+-- for the parallel #12 release (per-RFC invitation, owner-only) shipping
+-- in the same wave; the two features live in distinct tables
+-- (`user_invite_tokens` here vs. `rfc_invitations` there) so they
+-- coexist cleanly. Slot 016 was reserved+skipped by Session K during
+-- v0.9.0 integration; slot 017 is the v0.11.0 device-trust table.
+--
+-- Open-question decisions settled in this release (see CHANGELOG):
+--   * No `users` table changes — the brief floated `first_sign_in_at`
+--     / `last_seen_at IS NULL` as the "(pending invite)" discriminator,
+--     but the existing `users.last_seen_at` is NOT NULL with a
+--     `datetime('now')` default (migrations/001) and there is no
+--     `first_sign_in_at` column. Rather than land a schema migration to
+--     introduce one, the discriminator is the existence of an active
+--     (not-claimed, not-expired) row in `user_invite_tokens` joined on
+--     `invited_user_id`. The admin user-listing carries a
+--     `pending_invite` field populated via that join; on claim, the
+--     invite row's `claimed_at` populates and the badge clears.
+--     No new `permission_state` value is introduced either.
+--   * The token is opaque (random URL-safe string, bcrypt-hashed at
+--     rest), not a JWT, so admin revocation by row UPDATE works
+--     without distributing a key-rotation gesture.
+--   * The TTL is a constant (`INVITE_TOKEN_TTL_DAYS = 7` in
+--     `backend/app/invites.py`); env-var configurability is a follow-up.
+--   * Immediate-send (no admin-review-then-send queue) ships in this
+--     release; admin-preview is a future enhancement.
+--   * Bulk-invite (CSV paste) is deferred to a follow-up release;
+--     v0.17.0 is one-at-a-time.
+--
+-- Storage shape:
+--
+--   * `id` — surrogate key. Lets the admin "pending invites" listing
+--     address a row without leaking the token shape.
+--   * `email` — the address the invite was sent to (case-insensitive
+--     match at claim time, persisted verbatim for the audit trail).
+--   * `role` — the role the invitee inherits on first sign-in. Pinned
+--     via CHECK to the same set the §6.1 role flip accepts
+--     (`owner` / `admin` / `contributor`) so a future role-set drift
+--     fails loudly at insert rather than provisioning a ghost role.
+--   * `first_name` / `last_name` — captured at create time so the
+--     invitee skips the v0.8.0 capture-form step on first sign-in.
+--   * `custom_message` — optional free-text from the admin (max 500
+--     chars enforced at the API layer); embedded verbatim in the
+--     email body if present.
+--   * `token_hash` — bcrypt hash of the random opaque token. The
+--     raw token only ever lives in the outbound email link and the
+--     inbound claim body; server-side storage is the hash.
+--   * `expires_at` — `created_at + 7 days` (default at the app layer
+--     via `INVITE_TOKEN_TTL_DAYS`). A row past this stamp is dead;
+--     the claim path refuses with HTTP 410.
+--   * `created_at` — when the admin issued the invite.
+--   * `created_by_admin_id` — FK into users(id) for the admin who
+--     created the invite (no cascade; if the admin's row is deleted
+--     the invite history stays so the audit trail survives).
+--   * `claimed_at` — non-NULL once the invitee successfully claims.
+--     A second claim attempt against an already-claimed row returns
+--     HTTP 410.
+--   * `claimed_by_user_id` — FK into users(id) for the user row
+--     that consumed the token. In the common case this equals the
+--     freshly-provisioned row that was created at invite time; the
+--     FK lets the admin's "claimed" list join through.
+--   * `invited_user_id` — FK into users(id) for the pre-provisioned
+--     row. Created at invite time with `last_seen_at IS NULL` so the
+--     v0.9.0 admin user-management page can render a "(pending
+--     invite)" badge alongside existing users.
+--
+-- Indexing:
+--   * Unique index on `token_hash` documents the no-collision
+--     invariant (256 bits of CSPRNG entropy; collision is
+--     structurally impossible, the unique constraint catches a
+--     bug at insert time).
+--   * Index on `(email, claimed_at)` so the "is this email already
+--     invited?" pre-check the admin endpoint runs is a covering walk.
+--   * Index on `(created_by_admin_id, created_at DESC)` for the
+--     admin's "invites I've sent" listing.
+
+CREATE TABLE user_invite_tokens (
+    id                   INTEGER PRIMARY KEY AUTOINCREMENT,
+    email                TEXT NOT NULL,
+    role                 TEXT NOT NULL CHECK (role IN ('owner', 'admin', 'contributor')),
+    first_name           TEXT NOT NULL DEFAULT '',
+    last_name            TEXT NOT NULL DEFAULT '',
+    custom_message       TEXT NOT NULL DEFAULT '',
+    token_hash           TEXT NOT NULL,
+    expires_at           TEXT NOT NULL,
+    created_at           TEXT NOT NULL DEFAULT (datetime('now')),
+    created_by_admin_id  INTEGER NOT NULL REFERENCES users(id),
+    claimed_at           TEXT,
+    claimed_by_user_id   INTEGER REFERENCES users(id),
+    invited_user_id      INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE
+);
+
+CREATE UNIQUE INDEX idx_user_invite_tokens_hash ON user_invite_tokens (token_hash);
+CREATE INDEX idx_user_invite_tokens_email ON user_invite_tokens (email, claimed_at);
+CREATE INDEX idx_user_invite_tokens_admin ON user_invite_tokens (created_by_admin_id, created_at DESC);

backend/migrations/020_outbound_emails.sql

@@ -0,0 +1,30 @@
+-- v0.18.0 Slice 4: outbound_emails audit table.
+--
+-- Per the v0.18.0 email + webhook hygiene proposal §3, every send
+-- helper writes a row to this table before returning, regardless
+-- of outcome. status='sent' on success, 'failed' on exception,
+-- 'deferred' on the dev-fallback path (no SMTP_HOST configured).
+--
+-- The table is queried by `GET /api/admin/outbound-emails` to
+-- answer "did this person ever get their invite?" without having
+-- to grep VM logs, and by the v0.18.0 Slice 5 bounce-correlation
+-- hook (which looks up message_id when a POST lands at
+-- /api/webhooks/email-bounce and marks the matching row
+-- status='bounced').
+
+CREATE TABLE IF NOT EXISTS outbound_emails (
+    id              INTEGER PRIMARY KEY,
+    to_address      TEXT NOT NULL,
+    from_address    TEXT NOT NULL,
+    subject         TEXT NOT NULL,
+    kind            TEXT NOT NULL,     -- 'otc' | 'invite' | 'notification' | 'bundle' | 'digest' | 'rfc-invite'
+    sent_at         TEXT NOT NULL,     -- ISO 8601, time the send was attempted
+    status          TEXT NOT NULL,     -- 'sent' | 'failed' | 'deferred' | 'bounced'
+    error           TEXT,              -- exception class + message if status='failed'
+    notification_id INTEGER,           -- nullable FK to notifications.id for the watcher path
+    message_id      TEXT               -- the Message-ID header value, for bounce correlation
+);
+
+CREATE INDEX IF NOT EXISTS idx_outbound_emails_to        ON outbound_emails(to_address);
+CREATE INDEX IF NOT EXISTS idx_outbound_emails_sent_at   ON outbound_emails(sent_at);
+CREATE INDEX IF NOT EXISTS idx_outbound_emails_message   ON outbound_emails(message_id);

backend/migrations/021_proposed_use_case.sql

@@ -0,0 +1,47 @@
+-- Roadmap #26 (rfc-app v0.22.0): the optional "What will you be using
+-- this for?" capture on the two propose surfaces.
+--
+-- The roadmap's framing names "the rfcs table" and "the PR-metadata
+-- table" for a `proposed_use_case TEXT NULL` column. In this deployment
+-- those two surfaces are the cache tables `cached_rfcs` and `cached_prs`
+-- (002_cache.sql). We add the nullable column to each, matching the
+-- existing naming convention (no NOT NULL, no default — NULL is the
+-- "left blank" sentinel the view surfaces render tastefully).
+--
+-- BUT: those tables are *cache*, rebuilt from Gitea by the §4.1
+-- reconciler (cache.py). The reconciler's INSERT...ON CONFLICT DO UPDATE
+-- sets only the columns it knows about, so an unlisted column is
+-- preserved on the update path — yet a propose/open never *writes* the
+-- column through the cache (the write path is endpoint -> Gitea ->
+-- reconcile, and the reconciler does not carry this field). So the cache
+-- column alone would always read NULL.
+--
+-- The durable home is therefore a dedicated app-truth table the propose
+-- /open endpoints write directly (keyed by the PR number, which is the
+-- stable identity for both idea PRs and rfc_branch PRs) and the view
+-- endpoints read back. This is not cache — it is canonical and survives
+-- any reconcile. The cache columns are added too for parity with the
+-- roadmap's literal shape and for any future reconciler that learns to
+-- carry the field, but the side table is the source of truth read at
+-- view time.
+
+ALTER TABLE cached_rfcs ADD COLUMN proposed_use_case TEXT;
+ALTER TABLE cached_prs ADD COLUMN proposed_use_case TEXT;
+
+-- Canonical, reconcile-proof store. One row per propose/open that
+-- supplied a use case. `scope` distinguishes the propose-RFC surface
+-- ('rfc') from the propose-PR-against-an-RFC surface ('pr'); `pr_number`
+-- is the join key the endpoints already have in hand. NULL/omitted use
+-- cases simply never write a row here, so absence == "left blank".
+CREATE TABLE proposed_use_cases (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    scope           TEXT NOT NULL CHECK (scope IN ('rfc', 'pr')),
+    rfc_slug        TEXT NOT NULL,
+    pr_number       INTEGER NOT NULL,
+    use_case        TEXT NOT NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    UNIQUE (scope, pr_number)
+);
+
+CREATE INDEX idx_proposed_use_cases_lookup ON proposed_use_cases (scope, pr_number);
+CREATE INDEX idx_proposed_use_cases_slug ON proposed_use_cases (scope, rfc_slug);

backend/migrations/022_user_session_state.sql

@@ -0,0 +1,54 @@
+-- v0.23.0 / roadmap item #29: server-side sign-in state resume.
+--
+-- Track each authenticated user's last-viewed route + a small bag of
+-- "light" component state so that the *next* sign-in can land the user
+-- back where they left off, rather than always dropping them on the
+-- empty-state home view.
+--
+-- Storage shape (one row per user — per-user, NOT per-device, per the
+-- #29 "safe default"):
+--
+--   * `user_id` — PRIMARY KEY and FK into users(id) with cascade on
+--     delete. INTEGER to match users.id (INTEGER PRIMARY KEY
+--     AUTOINCREMENT). A deleted user automatically loses their stored
+--     resume state. One row per user means a later sign-in on any
+--     device resumes the most-recently-recorded route — the per-user
+--     model the roadmap asks for.
+--
+--   * `last_route` — the frontend pathname the user was last on
+--     (e.g. "/rfc/open-human-model"). TEXT, nullable until the first
+--     route-change POST lands. NEVER contains draft-buffer contents —
+--     it is a route only. See SPEC §6.2 "Sign-in state resume
+--     (privacy)".
+--
+--   * `last_route_state` — a JSON-encoded bag of *light* component
+--     state (scroll anchors, open-tab selection, filter chips, etc.).
+--     SQLite has no native JSONB; we store JSON as TEXT exactly as the
+--     rest of the app stores its JSON blobs (json.dumps / json.loads,
+--     cf. permission_events.details, actions.details). Nullable.
+--     PRIVACY INVARIANT: this column MUST NOT carry draft-buffer text,
+--     PR bodies, comment drafts, or any user-typed content — only
+--     ephemeral view state safe to replay. The PUT handler is the
+--     enforcement point; the column comment is the contract.
+--
+--   * `resume_enabled` — the per-user opt-out flag. 1 (default) means
+--     "resume me where I left off"; 0 means "always land on home". The
+--     PUT handler no-ops the upsert when this is 0, and the read path
+--     refuses to hand back a stored route when this is 0. A
+--     profile-settings toggle UI to flip this is a follow-up (the
+--     column + default-on behavior ship now); see CHANGELOG v0.23.0.
+--
+--   * `last_updated_at` — TEXT timestamp, app convention
+--     `datetime('now')`, matching device_trust.last_seen_at /
+--     users.last_seen_at. Refreshed on every successful upsert.
+--
+-- No new env vars. The debounce interval for the frontend route-change
+-- POST is a frontend constant (~1s), not a server knob.
+
+CREATE TABLE user_session_state (
+    user_id          INTEGER PRIMARY KEY REFERENCES users(id) ON DELETE CASCADE,
+    last_route       TEXT,
+    last_route_state TEXT,                        -- JSON-encoded light state, nullable
+    resume_enabled   INTEGER NOT NULL DEFAULT 1,
+    last_updated_at  TEXT NOT NULL DEFAULT (datetime('now'))
+);

backend/migrations/023_otc_verify_lockout.sql

@@ -0,0 +1,18 @@
+-- v0.25.0 / security audit 0026, finding H1.
+--
+-- The OTC verify path had no attempt-limit or lockout, unlike the
+-- passcode path (015_passcode.sql gave users.passcode_failed_attempts +
+-- passcode_locked_until). This table gives the OTC verify endpoint the
+-- same per-identity lockout shape. It is keyed by email rather than
+-- user_id because an OTC sign-in may not have a users row yet — the row
+-- is provisioned only on a *successful* verify, so the lockout state has
+-- to survive independently of it.
+--
+-- The per-IP rate limiter (app/ratelimit.py) is the primary brute-force
+-- defense; this table is the parity layer that mirrors the passcode
+-- lockout and persists across restarts.
+CREATE TABLE IF NOT EXISTS otc_verify_state (
+    email TEXT PRIMARY KEY,
+    failed_attempts INTEGER NOT NULL DEFAULT 0,
+    locked_until TEXT
+);

backend/migrations/024_contribution_requests.sql

@@ -0,0 +1,59 @@
+-- v0.29.0 / roadmap #28 Part 3 — offer-to-contribute-to-a-pending-RFC.
+--
+-- When the #28 scanner matches a term in submitted PR/comment text to a
+-- *pending* RFC (a super-draft: accepted-as-an-idea but not yet graduated
+-- to an active RFC), the reader is offered a "ask to contribute" popover.
+-- Submitting it lands a row here AND a notification in each owner's §15
+-- inbox; the owner can accept (which fires #12's owner-invite flow with
+-- the requester as the invitee) or decline (the requester is notified and
+-- the request closes).
+--
+-- A "pending RFC" is scoped to a super-draft (cached_rfcs.state =
+-- 'super-draft'): it is in cached_rfcs (so the rfc_invitations FK that the
+-- accept path reuses resolves), it carries owners (owners_json) to route
+-- the request to, and it already has a discussion/contribution surface to
+-- open. Pre-merge idea PRs (not yet in cached_rfcs, no contribution
+-- surface) are deliberately out of scope — see backend/app/rfc_links.py.
+--
+-- The request row is the persistent record; the inbox notification is the
+-- owner-facing actionable surface keyed back to it via `notification_id`.
+
+CREATE TABLE IF NOT EXISTS contribution_requests (
+    id                  INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug            TEXT NOT NULL
+                            REFERENCES cached_rfcs(slug) ON DELETE CASCADE,
+    requester_user_id   INTEGER NOT NULL
+                            REFERENCES users(id) ON DELETE CASCADE,
+    -- The term in the PR/comment text that surfaced the offer (e.g. the
+    -- super-draft's title). Carried for the owner's context line and the
+    -- requester's "what RFC" anchor; not a foreign key.
+    matched_term        TEXT NOT NULL,
+    -- The three contribute-request fields (§15 / #26 vocabulary).
+    -- `who_i_am` and `why` are required; `use_case` mirrors #26's
+    -- optional ground-truth field.
+    who_i_am            TEXT NOT NULL,
+    why                 TEXT NOT NULL,
+    use_case            TEXT,
+    status              TEXT NOT NULL DEFAULT 'pending'
+                            CHECK (status IN ('pending', 'accepted', 'declined')),
+    created_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    decided_at          TEXT,
+    decided_by_user_id  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    -- The rfc_invitations row minted on accept (the #12 reuse), and the
+    -- owner-facing notification row that carries the Accept/Decline action.
+    invitation_id       INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    notification_id     INTEGER REFERENCES notifications(id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_contribution_requests_rfc
+    ON contribution_requests(rfc_slug, status);
+
+CREATE INDEX IF NOT EXISTS idx_contribution_requests_requester
+    ON contribution_requests(requester_user_id, status);
+
+-- At most one open (pending) request per (RFC, requester): a second ask
+-- while one is still pending is a 409, not a duplicate row. A decided
+-- request (accepted/declined) does not block a fresh ask later.
+CREATE UNIQUE INDEX IF NOT EXISTS idx_contribution_requests_one_open
+    ON contribution_requests(rfc_slug, requester_user_id)
+    WHERE status = 'pending';

backend/migrations/025_retired_state.sql

@@ -0,0 +1,61 @@
+-- §3 / §13.7: add the `retired` soft-delete state to cached_rfcs.
+--
+-- SQLite cannot ALTER a CHECK constraint in place, so we rebuild the table
+-- with the expanded constraint and copy the rows across. cached_rfcs is a
+-- §4 cache (reconstructible from Gitea by the reconciler), and nothing
+-- holds a foreign key into it, so the rebuild is safe; we preserve the
+-- existing rows anyway to avoid a needless full re-read on upgrade.
+--
+-- The rebuilt table must carry EVERY column cached_rfcs has accumulated,
+-- including the ones added by later migrations via ALTER TABLE ADD COLUMN:
+--   009_per_rfc_models  -> models_json
+--   010_funder          -> funder_login
+--   021_proposed_use_case -> proposed_use_case
+-- They are appended last (matching the live column order) and copied
+-- across explicitly so nothing is dropped.
+--
+-- The migration runner wraps this file in a single BEGIN/COMMIT, so the
+-- swap is atomic.
+
+CREATE TABLE cached_rfcs_new (
+    slug                TEXT PRIMARY KEY,
+    title               TEXT NOT NULL,
+    state               TEXT NOT NULL CHECK (state IN ('super-draft', 'active', 'withdrawn', 'retired')),
+    rfc_id              TEXT,                -- 'RFC-NNNN' or NULL (NULL is also valid for an active RFC graduated without a number, §13.2)
+    repo                TEXT,                -- 'org/repo' or NULL; always NULL under the meta-only topology (§1)
+    proposed_by         TEXT,
+    proposed_at         TEXT,
+    graduated_at        TEXT,
+    graduated_by        TEXT,
+    owners_json         TEXT NOT NULL DEFAULT '[]',
+    arbiters_json       TEXT NOT NULL DEFAULT '[]',
+    tags_json           TEXT NOT NULL DEFAULT '[]',
+    body                TEXT,
+    body_sha            TEXT,
+    last_main_commit_at TEXT,
+    last_entry_commit_at TEXT,
+    updated_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    models_json         TEXT,                -- 009_per_rfc_models
+    funder_login        TEXT,                -- 010_funder
+    proposed_use_case   TEXT                 -- 021_proposed_use_case
+);
+
+INSERT INTO cached_rfcs_new
+    (slug, title, state, rfc_id, repo, proposed_by, proposed_at,
+     graduated_at, graduated_by, owners_json, arbiters_json, tags_json,
+     body, body_sha, last_main_commit_at, last_entry_commit_at, updated_at,
+     models_json, funder_login, proposed_use_case)
+SELECT
+     slug, title, state, rfc_id, repo, proposed_by, proposed_at,
+     graduated_at, graduated_by, owners_json, arbiters_json, tags_json,
+     body, body_sha, last_main_commit_at, last_entry_commit_at, updated_at,
+     models_json, funder_login, proposed_use_case
+  FROM cached_rfcs;
+
+DROP TABLE cached_rfcs;
+ALTER TABLE cached_rfcs_new RENAME TO cached_rfcs;
+
+CREATE INDEX idx_cached_rfcs_state ON cached_rfcs (state);
+CREATE INDEX idx_cached_rfcs_last_active ON cached_rfcs (
+    COALESCE(last_main_commit_at, last_entry_commit_at) DESC
+);

backend/migrations/026_projects.sql

@@ -0,0 +1,105 @@
+-- §22 (multi-project deployments) — Slice M1: the project spine.
+--
+-- A deployment now hosts one or more *projects*, each a corpus with its own
+-- content repo, slug/RFC-NNNN namespace, catalog, roster, and branding. The
+-- pre-multi-project single-corpus deployment is the N=1 case: this migration
+-- generates one 'default' project and stamps every existing RFC-scoped row
+-- to it, so the app keeps running exactly as before with the spine
+-- underneath (see docs/design/multi-project-spec.md §22.13).
+--
+-- STRATEGY — additive, no table rebuilds. Every slug-bearing table gets a
+-- `project_id TEXT NOT NULL DEFAULT 'default'` column. The constant default
+-- means every existing INSERT in the codebase that does not yet mention
+-- project_id keeps working and lands rows in the default project; no query
+-- breaks because, with a single project, slugs remain globally unique. The
+-- column carries no inline REFERENCES clause: SQLite's ALTER TABLE ADD
+-- COLUMN forbids a FK column with a non-NULL default. project_id referential
+-- integrity is therefore enforced at the app layer for now; the FK lands
+-- with the table rebuilds below.
+--
+-- ============================================================================
+-- DEFERRED to the slice that activates project #2 (M3/M4). Until a second
+-- project exists these are correct as-is; the moment two projects can share a
+-- slug or a Gitea PR number they become cross-project collision bugs and MUST
+-- be rebuilt (SQLite needs a create-copy-drop-rename per table) to fold
+-- project_id into the key, and to add the project_id FK:
+--   * cached_rfcs            PRIMARY KEY (slug)                  -> (project_id, slug)
+--   * cached_branches        UNIQUE (rfc_slug, branch_name)      -> +project_id
+--   * branch_visibility      UNIQUE (rfc_slug, branch_name)      -> +project_id
+--   * branch_contribute_grants UNIQUE (rfc_slug, branch_name, grantee_user_id) -> +project_id
+--   * stars                  UNIQUE (user_id, rfc_slug)          -> +project_id
+--   * watches                UNIQUE (user_id, rfc_slug)          -> +project_id
+--   * pr_seen                UNIQUE (user_id, rfc_slug, pr_number) -> +project_id
+--   * branch_chat_seen       UNIQUE (user_id, rfc_slug, branch_name) -> +project_id
+--   * funder_consents        PRIMARY KEY (user_id, rfc_slug)      -> +project_id
+--   * rfc_collaborators      UNIQUE INDEX (rfc_slug, user_id)     -> +project_id
+--   * contribution_requests  UNIQUE INDEX (rfc_slug, requester_user_id) WHERE pending -> +project_id
+--   * proposed_use_cases     UNIQUE (scope, pr_number)           -> +project_id
+--                            (PR numbers are per-content-repo = per-project)
+-- cached_prs UNIQUE (repo, pr_number) is already globally unique (repo is the
+-- full 'org/repo' string, distinct per project) and needs no rebuild.
+-- ============================================================================
+
+-- The project registry cache (mirrored from the git registry by the M3
+-- reconciler; rows are never written from user actions). content_repo is
+-- NULL until the mirror — or the M1 startup backfill (§22.13 step 1) — sets
+-- it from the deployment's configured repo.
+CREATE TABLE IF NOT EXISTS projects (
+    id            TEXT PRIMARY KEY,
+    name          TEXT NOT NULL,
+    content_repo  TEXT,
+    visibility    TEXT NOT NULL DEFAULT 'gated'
+                      CHECK (visibility IN ('gated', 'public', 'unlisted')),
+    config_json   TEXT,
+    registry_sha  TEXT,
+    created_at    TEXT NOT NULL DEFAULT (datetime('now')),
+    updated_at    TEXT NOT NULL DEFAULT (datetime('now'))
+);
+
+-- The default project. visibility='public' preserves the pre-multi-project
+-- open-by-default posture (§22.5, §22.13). name is a placeholder the startup
+-- backfill / registry overwrites with the deployment's display name.
+INSERT OR IGNORE INTO projects (id, name, visibility)
+    VALUES ('default', 'default', 'public');
+
+-- Per-(user, project) membership and the §22.6 middle-tier role. This is the
+-- new tier between the §6.1 deployment role (users.role, now deployment-scope
+-- only) and the §6.3 per-RFC authority.
+CREATE TABLE IF NOT EXISTS project_members (
+    project_id  TEXT NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+    user_id     INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role        TEXT NOT NULL DEFAULT 'project_viewer'
+                    CHECK (role IN ('project_admin', 'project_contributor', 'project_viewer')),
+    granted_by  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    granted_at  TEXT NOT NULL DEFAULT (datetime('now')),
+    PRIMARY KEY (project_id, user_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_project_members_user ON project_members(user_id);
+
+-- The project_id spine across every slug-bearing table. Backfills existing
+-- rows to 'default' via the constant column default.
+ALTER TABLE cached_rfcs              ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE cached_branches          ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE cached_prs               ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE branch_visibility        ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE branch_contribute_grants ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE stars                    ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE threads                  ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE changes                  ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE pr_seen                  ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE branch_chat_seen         ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE watches                  ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE notifications            ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE actions                  ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE pr_resolution_branches   ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE funder_consents          ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE rfc_invitations          ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE rfc_collaborators        ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE proposed_use_cases       ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+ALTER TABLE contribution_requests    ADD COLUMN project_id TEXT NOT NULL DEFAULT 'default';
+
+-- The catalog/directory lookup the M3 surfaces will make (RFCs in a project).
+-- The per-table composite-key rebuilds in the DEFERRED block above will add
+-- their own (project_id, …) indexes when they land.
+CREATE INDEX IF NOT EXISTS idx_cached_rfcs_project ON cached_rfcs(project_id);

backend/migrations/027_projects_runtime_config.sql

@@ -0,0 +1,31 @@
+-- §22 M3 (Plan A) — additive registry/runtime-config schema.
+--
+-- This is the additive half of M3's backend. It adds the project `type` and
+-- `initial_state` columns (mirrored from the registry), the deployment
+-- singleton (deployment name/tagline mirrored from the registry), and the
+-- §22.4c review columns on cached_rfcs. NO table rebuilds: the §22.13 PK
+-- rebuilds and the default->slug re-stamp ride a later migration (Plan B),
+-- just before a second project can collide (see migration 026's DEFERRED
+-- block and docs/superpowers/specs/2026-06-03-m3-backend-design.md §1/§6).
+
+ALTER TABLE projects ADD COLUMN type TEXT NOT NULL DEFAULT 'document'
+    CHECK (type IN ('document', 'specification', 'bdd'));
+ALTER TABLE projects ADD COLUMN initial_state TEXT NOT NULL DEFAULT 'super-draft'
+    CHECK (initial_state IN ('super-draft', 'active'));
+
+-- Deployment-level identity (name, tagline) mirrored from the registry's
+-- `deployment:` block. A singleton: the CHECK pins it to one row.
+CREATE TABLE IF NOT EXISTS deployment (
+    id           INTEGER PRIMARY KEY CHECK (id = 1),
+    name         TEXT,
+    tagline      TEXT,
+    registry_sha TEXT,
+    updated_at   TEXT NOT NULL DEFAULT (datetime('now'))
+);
+INSERT OR IGNORE INTO deployment (id) VALUES (1);
+
+-- §22.4c review flag + provenance. unreviewed is git-truth (mirrored from
+-- entry frontmatter); it survives a cache rebuild like `state` does.
+ALTER TABLE cached_rfcs ADD COLUMN unreviewed INTEGER NOT NULL DEFAULT 0;
+ALTER TABLE cached_rfcs ADD COLUMN reviewed_at TEXT;
+ALTER TABLE cached_rfcs ADD COLUMN reviewed_by TEXT;

backend/migrations/028_project_scoped_keys.sql

@@ -0,0 +1,276 @@
+-- migrate:no-foreign-keys
+--
+-- §22.13 / §22.4 — fold project_id into the slug-keyed PRIMARY KEY / UNIQUE
+-- constraints that migration 026 deliberately left global, so a *second*
+-- project can hold an entry with the same slug as the first. M1 (026) added
+-- project_id additively (no rebuild); this is the rebuild that activates
+-- project #2, enumerated in 026's header.
+--
+-- SQLite can't ALTER a PK/UNIQUE in place, so each table is rebuilt by the
+-- official procedure: create `<t>__new` with the new constraint, copy, DROP
+-- the live table, rename `<t>__new` -> `<t>`, recreate its indexes. FK
+-- enforcement is OFF for the whole file (the `migrate:no-foreign-keys` marker
+-- above tells the runner to toggle it and run foreign_key_check after).
+--
+-- DROP-the-live-table (rather than rename-live-to-__old) is deliberate: SQLite
+-- rewrites child FK references when you RENAME a *referenced* table, so we drop
+-- the old cached_rfcs (allowed with FK off) and rename the temp in. cached_rfcs
+-- is rebuilt FIRST so rfc_collaborators / contribution_requests can re-point
+-- their FK at its new composite (project_id, slug) key.
+
+-- ── cached_rfcs: PRIMARY KEY (slug) -> (project_id, slug) ──────────────────
+CREATE TABLE cached_rfcs__new (
+    slug                TEXT NOT NULL,
+    title               TEXT NOT NULL,
+    state               TEXT NOT NULL CHECK (state IN ('super-draft', 'active', 'withdrawn', 'retired')),
+    rfc_id              TEXT,
+    repo                TEXT,
+    proposed_by         TEXT,
+    proposed_at         TEXT,
+    graduated_at        TEXT,
+    graduated_by        TEXT,
+    owners_json         TEXT NOT NULL DEFAULT '[]',
+    arbiters_json       TEXT NOT NULL DEFAULT '[]',
+    tags_json           TEXT NOT NULL DEFAULT '[]',
+    body                TEXT,
+    body_sha            TEXT,
+    last_main_commit_at TEXT,
+    last_entry_commit_at TEXT,
+    updated_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    models_json         TEXT,
+    funder_login        TEXT,
+    proposed_use_case   TEXT,
+    project_id          TEXT NOT NULL DEFAULT 'default',
+    unreviewed          INTEGER NOT NULL DEFAULT 0,
+    reviewed_at         TEXT,
+    reviewed_by         TEXT,
+    PRIMARY KEY (project_id, slug)
+);
+INSERT INTO cached_rfcs__new SELECT * FROM cached_rfcs;
+DROP TABLE cached_rfcs;
+ALTER TABLE cached_rfcs__new RENAME TO cached_rfcs;
+CREATE INDEX idx_cached_rfcs_state ON cached_rfcs (state);
+CREATE INDEX idx_cached_rfcs_last_active ON cached_rfcs (
+    COALESCE(last_main_commit_at, last_entry_commit_at) DESC
+);
+CREATE INDEX idx_cached_rfcs_project ON cached_rfcs(project_id);
+
+-- ── rfc_invitations: FK rfc_slug -> cached_rfcs(slug) becomes composite ────
+-- (no key change of its own, but its single-column FK to cached_rfcs is now a
+-- mismatch against the composite PK, so it must be rebuilt too). Rebuilt after
+-- cached_rfcs (its FK target) and before the two tables that FK rfc_invitations.
+CREATE TABLE rfc_invitations__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug                TEXT NOT NULL,
+    inviter_user_id         INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    invitee_email           TEXT NOT NULL,
+    role_in_rfc             TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    status                  TEXT NOT NULL DEFAULT 'pending'
+        CHECK (status IN ('pending', 'accepted', 'revoked', 'expired')),
+    token                   TEXT NOT NULL,
+    expires_at              TEXT NOT NULL,
+    created_at              TEXT NOT NULL DEFAULT (datetime('now')),
+    accepted_at             TEXT,
+    accepted_by_user_id     INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    project_id              TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (project_id, rfc_slug) REFERENCES cached_rfcs(project_id, slug) ON DELETE CASCADE
+);
+INSERT INTO rfc_invitations__new SELECT * FROM rfc_invitations;
+DROP TABLE rfc_invitations;
+ALTER TABLE rfc_invitations__new RENAME TO rfc_invitations;
+CREATE UNIQUE INDEX idx_rfc_invitations_token ON rfc_invitations (token);
+CREATE INDEX idx_rfc_invitations_rfc_status ON rfc_invitations (rfc_slug, status);
+CREATE INDEX idx_rfc_invitations_email_status ON rfc_invitations (invitee_email, status);
+
+-- ── cached_branches: UNIQUE (rfc_slug, branch_name) -> +project_id ─────────
+CREATE TABLE cached_branches__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    head_sha        TEXT,
+    state           TEXT NOT NULL DEFAULT 'open' CHECK (state IN ('open', 'closed', 'deleted')),
+    pinned          INTEGER NOT NULL DEFAULT 0,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    last_commit_at  TEXT,
+    closed_at       TEXT,
+    project_id      TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, rfc_slug, branch_name)
+);
+INSERT INTO cached_branches__new SELECT * FROM cached_branches;
+DROP TABLE cached_branches;
+ALTER TABLE cached_branches__new RENAME TO cached_branches;
+CREATE INDEX idx_cached_branches_rfc ON cached_branches (rfc_slug, state);
+
+-- ── branch_visibility: UNIQUE (rfc_slug, branch_name) -> +project_id ───────
+CREATE TABLE branch_visibility__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    read_public     INTEGER NOT NULL DEFAULT 1,
+    contribute_mode TEXT NOT NULL DEFAULT 'just-me' CHECK (contribute_mode IN ('just-me', 'specific', 'any-contributor')),
+    project_id      TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, rfc_slug, branch_name)
+);
+INSERT INTO branch_visibility__new SELECT * FROM branch_visibility;
+DROP TABLE branch_visibility;
+ALTER TABLE branch_visibility__new RENAME TO branch_visibility;
+
+-- ── branch_contribute_grants: UNIQUE (rfc_slug, branch_name, grantee) -> +pid
+CREATE TABLE branch_contribute_grants__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    grantee_user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    granted_by      INTEGER NOT NULL REFERENCES users(id) ON DELETE SET NULL,
+    granted_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id      TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, rfc_slug, branch_name, grantee_user_id)
+);
+INSERT INTO branch_contribute_grants__new SELECT * FROM branch_contribute_grants;
+DROP TABLE branch_contribute_grants;
+ALTER TABLE branch_contribute_grants__new RENAME TO branch_contribute_grants;
+CREATE INDEX idx_grants_lookup ON branch_contribute_grants (rfc_slug, branch_name);
+CREATE INDEX idx_grants_grantee ON branch_contribute_grants (grantee_user_id);
+
+-- ── stars: UNIQUE (user_id, rfc_slug) -> +project_id ───────────────────────
+CREATE TABLE stars__new (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id     INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug    TEXT NOT NULL,
+    starred_at  TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id  TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, user_id, rfc_slug)
+);
+INSERT INTO stars__new SELECT * FROM stars;
+DROP TABLE stars;
+ALTER TABLE stars__new RENAME TO stars;
+CREATE INDEX idx_stars_user ON stars (user_id);
+CREATE INDEX idx_stars_rfc ON stars (rfc_slug);
+
+-- ── watches: UNIQUE (user_id, rfc_slug) -> +project_id ─────────────────────
+CREATE TABLE watches__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    state                   TEXT NOT NULL CHECK (state IN ('watching', 'following', 'muted')),
+    set_by                  TEXT NOT NULL CHECK (set_by IN ('auto', 'explicit')),
+    set_at                  TEXT NOT NULL DEFAULT (datetime('now')),
+    last_participation_at   TEXT,
+    project_id              TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, user_id, rfc_slug)
+);
+INSERT INTO watches__new SELECT * FROM watches;
+DROP TABLE watches;
+ALTER TABLE watches__new RENAME TO watches;
+CREATE INDEX idx_watches_user ON watches (user_id);
+CREATE INDEX idx_watches_rfc ON watches (rfc_slug);
+CREATE INDEX idx_watches_decay ON watches (state, last_participation_at);
+
+-- ── pr_seen: UNIQUE (user_id, rfc_slug, pr_number) -> +project_id ──────────
+CREATE TABLE pr_seen__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    pr_number               INTEGER NOT NULL,
+    last_seen_commit_sha    TEXT,
+    last_seen_message_id    INTEGER REFERENCES thread_messages(id) ON DELETE SET NULL,
+    seen_at                 TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id              TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, user_id, rfc_slug, pr_number)
+);
+INSERT INTO pr_seen__new SELECT * FROM pr_seen;
+DROP TABLE pr_seen;
+ALTER TABLE pr_seen__new RENAME TO pr_seen;
+
+-- ── branch_chat_seen: UNIQUE (user_id, rfc_slug, branch_name) -> +project_id
+CREATE TABLE branch_chat_seen__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    branch_name             TEXT NOT NULL,
+    last_seen_message_id    INTEGER REFERENCES thread_messages(id) ON DELETE SET NULL,
+    seen_at                 TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id              TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, user_id, rfc_slug, branch_name)
+);
+INSERT INTO branch_chat_seen__new SELECT * FROM branch_chat_seen;
+DROP TABLE branch_chat_seen;
+ALTER TABLE branch_chat_seen__new RENAME TO branch_chat_seen;
+
+-- ── funder_consents: PRIMARY KEY (user_id, rfc_slug) -> +project_id ────────
+CREATE TABLE funder_consents__new (
+    user_id     INTEGER NOT NULL,
+    rfc_slug    TEXT    NOT NULL,
+    created_at  TEXT    NOT NULL DEFAULT (datetime('now')),
+    project_id  TEXT    NOT NULL DEFAULT 'default',
+    PRIMARY KEY (project_id, user_id, rfc_slug),
+    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+INSERT INTO funder_consents__new SELECT * FROM funder_consents;
+DROP TABLE funder_consents;
+ALTER TABLE funder_consents__new RENAME TO funder_consents;
+CREATE INDEX idx_funder_consents_slug ON funder_consents (rfc_slug);
+
+-- ── rfc_collaborators: UNIQUE idx (rfc_slug, user_id) -> +project_id;
+--     FK rfc_slug -> cached_rfcs(slug) becomes composite (project_id, rfc_slug)
+CREATE TABLE rfc_collaborators__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    user_id         INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role_in_rfc     TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    invitation_id   INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id      TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (project_id, rfc_slug) REFERENCES cached_rfcs(project_id, slug) ON DELETE CASCADE
+);
+INSERT INTO rfc_collaborators__new SELECT * FROM rfc_collaborators;
+DROP TABLE rfc_collaborators;
+ALTER TABLE rfc_collaborators__new RENAME TO rfc_collaborators;
+CREATE UNIQUE INDEX idx_rfc_collaborators_unique ON rfc_collaborators (project_id, rfc_slug, user_id);
+CREATE INDEX idx_rfc_collaborators_user ON rfc_collaborators (user_id);
+
+-- ── contribution_requests: UNIQUE idx (rfc_slug, requester) WHERE pending
+--     -> +project_id; FK rfc_slug -> cached_rfcs(slug) becomes composite.
+CREATE TABLE contribution_requests__new (
+    id                  INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug            TEXT NOT NULL,
+    requester_user_id   INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    matched_term        TEXT NOT NULL,
+    who_i_am            TEXT NOT NULL,
+    why                 TEXT NOT NULL,
+    use_case            TEXT,
+    status              TEXT NOT NULL DEFAULT 'pending'
+                            CHECK (status IN ('pending', 'accepted', 'declined')),
+    created_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    decided_at          TEXT,
+    decided_by_user_id  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    invitation_id       INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    notification_id     INTEGER REFERENCES notifications(id) ON DELETE SET NULL,
+    project_id          TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (project_id, rfc_slug) REFERENCES cached_rfcs(project_id, slug) ON DELETE CASCADE
+);
+INSERT INTO contribution_requests__new SELECT * FROM contribution_requests;
+DROP TABLE contribution_requests;
+ALTER TABLE contribution_requests__new RENAME TO contribution_requests;
+CREATE INDEX idx_contribution_requests_rfc ON contribution_requests(rfc_slug, status);
+CREATE INDEX idx_contribution_requests_requester ON contribution_requests(requester_user_id, status);
+CREATE UNIQUE INDEX idx_contribution_requests_one_open
+    ON contribution_requests(project_id, rfc_slug, requester_user_id)
+    WHERE status = 'pending';
+
+-- ── proposed_use_cases: UNIQUE (scope, pr_number) -> +project_id ───────────
+CREATE TABLE proposed_use_cases__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    scope           TEXT NOT NULL CHECK (scope IN ('rfc', 'pr')),
+    rfc_slug        TEXT NOT NULL,
+    pr_number       INTEGER NOT NULL,
+    use_case        TEXT NOT NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    project_id      TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (project_id, scope, pr_number)
+);
+INSERT INTO proposed_use_cases__new SELECT * FROM proposed_use_cases;
+DROP TABLE proposed_use_cases;
+ALTER TABLE proposed_use_cases__new RENAME TO proposed_use_cases;
+CREATE INDEX idx_proposed_use_cases_lookup ON proposed_use_cases (scope, pr_number);
+CREATE INDEX idx_proposed_use_cases_slug ON proposed_use_cases (scope, rfc_slug);

backend/migrations/029_collections.sql

@@ -0,0 +1,427 @@
+-- migrate:no-foreign-keys
+--
+-- §22 three-tier refactor — S1. Insert a *collection* grain beneath project.
+--
+--   (1) a `collections` table beneath `projects`;
+--   (2) move the per-corpus fields (type, initial_state) down from `projects`
+--       (projects keeps id, name, content_repo, visibility, config_json, …);
+--   (3) one default collection per project (id='default' for the standard
+--       single-project deployment, subfolder = repo root), inheriting the
+--       project's type / initial_state / visibility;
+--   (4) re-key the 13 entry-corpus tables (project_id, slug) -> (collection_id,
+--       slug) via the migration-028 rebuild pattern, mapping each row to its
+--       project's default collection by JOIN;
+--   (5) generalise project_members -> memberships(scope_type ∈ {project,
+--       collection}, scope_id, …), collapsing the role enum to {owner,
+--       contributor} (§B.3).
+--
+-- SQLite can't ALTER a PK/UNIQUE in place, so each keyed table is rebuilt by the
+-- official create-copy-drop-rename procedure. FK enforcement is OFF for the file
+-- (the `migrate:no-foreign-keys` marker tells the runner to toggle it and run
+-- foreign_key_check after). cached_rfcs is rebuilt FIRST so the child tables can
+-- re-point their composite FK at its new (collection_id, slug) key.
+--
+-- The tables 026 tagged with project_id but 028 did NOT key (threads, changes,
+-- notifications, actions, pr_resolution_branches, cached_prs) keep project_id —
+-- they carry a project-grain tag, untouched in S1. See
+-- docs/design/2026-06-05-three-tier-projects-collections.md §A.6 / Part E.
+
+-- ── collections: the new typed-corpus grain beneath projects ───────────────
+CREATE TABLE collections (
+    id            TEXT NOT NULL,
+    project_id    TEXT NOT NULL REFERENCES projects(id) ON DELETE CASCADE,
+    type          TEXT NOT NULL DEFAULT 'document'
+                      CHECK (type IN ('document', 'specification', 'bdd')),
+    subfolder     TEXT NOT NULL DEFAULT '',
+    initial_state TEXT NOT NULL DEFAULT 'super-draft'
+                      CHECK (initial_state IN ('super-draft', 'active')),
+    visibility    TEXT NOT NULL DEFAULT 'gated'
+                      CHECK (visibility IN ('gated', 'public', 'unlisted')),
+    name          TEXT,
+    registry_sha  TEXT,
+    created_at    TEXT NOT NULL DEFAULT (datetime('now')),
+    updated_at    TEXT NOT NULL DEFAULT (datetime('now')),
+    PRIMARY KEY (id)
+);
+CREATE INDEX idx_collections_project ON collections(project_id);
+
+-- One default collection per project. id='default' for the standard
+-- single-project deployment (a stable literal across deploy histories); the
+-- project_id is used as a unique fallback id only if a non-standard
+-- multi-project deployment migrates (pre-S5; avoids a PK collision).
+INSERT INTO collections (id, project_id, type, subfolder, initial_state, visibility, name)
+SELECT
+    CASE WHEN (SELECT COUNT(*) FROM projects) <= 1 THEN 'default' ELSE p.id END,
+    p.id, p.type, '', p.initial_state, p.visibility, p.name
+FROM projects p;
+
+-- ── projects: rebuild to DROP the per-corpus fields (type, initial_state) ───
+CREATE TABLE projects__new (
+    id            TEXT PRIMARY KEY,
+    name          TEXT NOT NULL,
+    content_repo  TEXT,
+    visibility    TEXT NOT NULL DEFAULT 'gated'
+                      CHECK (visibility IN ('gated', 'public', 'unlisted')),
+    config_json   TEXT,
+    registry_sha  TEXT,
+    created_at    TEXT NOT NULL DEFAULT (datetime('now')),
+    updated_at    TEXT NOT NULL DEFAULT (datetime('now'))
+);
+INSERT INTO projects__new (id, name, content_repo, visibility, config_json, registry_sha, created_at, updated_at)
+SELECT id, name, content_repo, visibility, config_json, registry_sha, created_at, updated_at FROM projects;
+DROP TABLE projects;
+ALTER TABLE projects__new RENAME TO projects;
+
+-- ── cached_rfcs: PRIMARY KEY (project_id, slug) -> (collection_id, slug) ────
+CREATE TABLE cached_rfcs__new (
+    slug                TEXT NOT NULL,
+    title               TEXT NOT NULL,
+    state               TEXT NOT NULL CHECK (state IN ('super-draft', 'active', 'withdrawn', 'retired')),
+    rfc_id              TEXT,
+    repo                TEXT,
+    proposed_by         TEXT,
+    proposed_at         TEXT,
+    graduated_at        TEXT,
+    graduated_by        TEXT,
+    owners_json         TEXT NOT NULL DEFAULT '[]',
+    arbiters_json       TEXT NOT NULL DEFAULT '[]',
+    tags_json           TEXT NOT NULL DEFAULT '[]',
+    body                TEXT,
+    body_sha            TEXT,
+    last_main_commit_at TEXT,
+    last_entry_commit_at TEXT,
+    updated_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    models_json         TEXT,
+    funder_login        TEXT,
+    proposed_use_case   TEXT,
+    collection_id       TEXT NOT NULL DEFAULT 'default' REFERENCES collections(id),
+    unreviewed          INTEGER NOT NULL DEFAULT 0,
+    reviewed_at         TEXT,
+    reviewed_by         TEXT,
+    PRIMARY KEY (collection_id, slug)
+);
+INSERT INTO cached_rfcs__new
+    (slug, title, state, rfc_id, repo, proposed_by, proposed_at, graduated_at,
+     graduated_by, owners_json, arbiters_json, tags_json, body, body_sha,
+     last_main_commit_at, last_entry_commit_at, updated_at, models_json,
+     funder_login, proposed_use_case, collection_id, unreviewed, reviewed_at, reviewed_by)
+SELECT
+    r.slug, r.title, r.state, r.rfc_id, r.repo, r.proposed_by, r.proposed_at, r.graduated_at,
+    r.graduated_by, r.owners_json, r.arbiters_json, r.tags_json, r.body, r.body_sha,
+    r.last_main_commit_at, r.last_entry_commit_at, r.updated_at, r.models_json,
+    r.funder_login, r.proposed_use_case,
+    (SELECT c.id FROM collections c WHERE c.project_id = r.project_id LIMIT 1),
+    r.unreviewed, r.reviewed_at, r.reviewed_by
+FROM cached_rfcs r;
+DROP TABLE cached_rfcs;
+ALTER TABLE cached_rfcs__new RENAME TO cached_rfcs;
+CREATE INDEX idx_cached_rfcs_state ON cached_rfcs (state);
+CREATE INDEX idx_cached_rfcs_last_active ON cached_rfcs (
+    COALESCE(last_main_commit_at, last_entry_commit_at) DESC
+);
+CREATE INDEX idx_cached_rfcs_collection ON cached_rfcs(collection_id);
+
+-- ── rfc_invitations: single-col FK -> composite (collection_id, rfc_slug) ───
+CREATE TABLE rfc_invitations__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug                TEXT NOT NULL,
+    inviter_user_id         INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    invitee_email           TEXT NOT NULL,
+    role_in_rfc             TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    status                  TEXT NOT NULL DEFAULT 'pending'
+        CHECK (status IN ('pending', 'accepted', 'revoked', 'expired')),
+    token                   TEXT NOT NULL,
+    expires_at              TEXT NOT NULL,
+    created_at              TEXT NOT NULL DEFAULT (datetime('now')),
+    accepted_at             TEXT,
+    accepted_by_user_id     INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    collection_id           TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (collection_id, rfc_slug) REFERENCES cached_rfcs(collection_id, slug) ON DELETE CASCADE
+);
+INSERT INTO rfc_invitations__new
+    (id, rfc_slug, inviter_user_id, invitee_email, role_in_rfc, status, token,
+     expires_at, created_at, accepted_at, accepted_by_user_id, collection_id)
+SELECT
+    i.id, i.rfc_slug, i.inviter_user_id, i.invitee_email, i.role_in_rfc, i.status, i.token,
+    i.expires_at, i.created_at, i.accepted_at, i.accepted_by_user_id,
+    (SELECT c.id FROM collections c WHERE c.project_id = i.project_id LIMIT 1)
+FROM rfc_invitations i;
+DROP TABLE rfc_invitations;
+ALTER TABLE rfc_invitations__new RENAME TO rfc_invitations;
+CREATE UNIQUE INDEX idx_rfc_invitations_token ON rfc_invitations (token);
+CREATE INDEX idx_rfc_invitations_rfc_status ON rfc_invitations (rfc_slug, status);
+CREATE INDEX idx_rfc_invitations_email_status ON rfc_invitations (invitee_email, status);
+
+-- ── cached_branches: UNIQUE (project_id, rfc_slug, branch_name) -> collection
+CREATE TABLE cached_branches__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    head_sha        TEXT,
+    state           TEXT NOT NULL DEFAULT 'open' CHECK (state IN ('open', 'closed', 'deleted')),
+    pinned          INTEGER NOT NULL DEFAULT 0,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    last_commit_at  TEXT,
+    closed_at       TEXT,
+    collection_id   TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, rfc_slug, branch_name)
+);
+INSERT INTO cached_branches__new
+    (id, rfc_slug, branch_name, head_sha, state, pinned, created_at, last_commit_at, closed_at, collection_id)
+SELECT
+    b.id, b.rfc_slug, b.branch_name, b.head_sha, b.state, b.pinned, b.created_at, b.last_commit_at, b.closed_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = b.project_id LIMIT 1)
+FROM cached_branches b;
+DROP TABLE cached_branches;
+ALTER TABLE cached_branches__new RENAME TO cached_branches;
+CREATE INDEX idx_cached_branches_rfc ON cached_branches (rfc_slug, state);
+
+-- ── branch_visibility: UNIQUE (project_id, rfc_slug, branch_name) -> collection
+CREATE TABLE branch_visibility__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    read_public     INTEGER NOT NULL DEFAULT 1,
+    contribute_mode TEXT NOT NULL DEFAULT 'just-me' CHECK (contribute_mode IN ('just-me', 'specific', 'any-contributor')),
+    collection_id   TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, rfc_slug, branch_name)
+);
+INSERT INTO branch_visibility__new
+    (id, rfc_slug, branch_name, read_public, contribute_mode, collection_id)
+SELECT
+    v.id, v.rfc_slug, v.branch_name, v.read_public, v.contribute_mode,
+    (SELECT c.id FROM collections c WHERE c.project_id = v.project_id LIMIT 1)
+FROM branch_visibility v;
+DROP TABLE branch_visibility;
+ALTER TABLE branch_visibility__new RENAME TO branch_visibility;
+
+-- ── branch_contribute_grants: UNIQUE (..., grantee) -> +collection_id ───────
+CREATE TABLE branch_contribute_grants__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    branch_name     TEXT NOT NULL,
+    grantee_user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    granted_by      INTEGER NOT NULL REFERENCES users(id) ON DELETE SET NULL,
+    granted_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id   TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, rfc_slug, branch_name, grantee_user_id)
+);
+INSERT INTO branch_contribute_grants__new
+    (id, rfc_slug, branch_name, grantee_user_id, granted_by, granted_at, collection_id)
+SELECT
+    g.id, g.rfc_slug, g.branch_name, g.grantee_user_id, g.granted_by, g.granted_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = g.project_id LIMIT 1)
+FROM branch_contribute_grants g;
+DROP TABLE branch_contribute_grants;
+ALTER TABLE branch_contribute_grants__new RENAME TO branch_contribute_grants;
+CREATE INDEX idx_grants_lookup ON branch_contribute_grants (rfc_slug, branch_name);
+CREATE INDEX idx_grants_grantee ON branch_contribute_grants (grantee_user_id);
+
+-- ── stars: UNIQUE (project_id, user_id, rfc_slug) -> collection_id ──────────
+CREATE TABLE stars__new (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id     INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug    TEXT NOT NULL,
+    starred_at  TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id  TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, user_id, rfc_slug)
+);
+INSERT INTO stars__new (id, user_id, rfc_slug, starred_at, collection_id)
+SELECT s.id, s.user_id, s.rfc_slug, s.starred_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = s.project_id LIMIT 1)
+FROM stars s;
+DROP TABLE stars;
+ALTER TABLE stars__new RENAME TO stars;
+CREATE INDEX idx_stars_user ON stars (user_id);
+CREATE INDEX idx_stars_rfc ON stars (rfc_slug);
+
+-- ── watches: UNIQUE (project_id, user_id, rfc_slug) -> collection_id ────────
+CREATE TABLE watches__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    state                   TEXT NOT NULL CHECK (state IN ('watching', 'following', 'muted')),
+    set_by                  TEXT NOT NULL CHECK (set_by IN ('auto', 'explicit')),
+    set_at                  TEXT NOT NULL DEFAULT (datetime('now')),
+    last_participation_at   TEXT,
+    collection_id           TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, user_id, rfc_slug)
+);
+INSERT INTO watches__new
+    (id, user_id, rfc_slug, state, set_by, set_at, last_participation_at, collection_id)
+SELECT
+    w.id, w.user_id, w.rfc_slug, w.state, w.set_by, w.set_at, w.last_participation_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = w.project_id LIMIT 1)
+FROM watches w;
+DROP TABLE watches;
+ALTER TABLE watches__new RENAME TO watches;
+CREATE INDEX idx_watches_user ON watches (user_id);
+CREATE INDEX idx_watches_rfc ON watches (rfc_slug);
+CREATE INDEX idx_watches_decay ON watches (state, last_participation_at);
+
+-- ── pr_seen: UNIQUE (project_id, user_id, rfc_slug, pr_number) -> collection ─
+CREATE TABLE pr_seen__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    pr_number               INTEGER NOT NULL,
+    last_seen_commit_sha    TEXT,
+    last_seen_message_id    INTEGER REFERENCES thread_messages(id) ON DELETE SET NULL,
+    seen_at                 TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id           TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, user_id, rfc_slug, pr_number)
+);
+INSERT INTO pr_seen__new
+    (id, user_id, rfc_slug, pr_number, last_seen_commit_sha, last_seen_message_id, seen_at, collection_id)
+SELECT
+    p.id, p.user_id, p.rfc_slug, p.pr_number, p.last_seen_commit_sha, p.last_seen_message_id, p.seen_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = p.project_id LIMIT 1)
+FROM pr_seen p;
+DROP TABLE pr_seen;
+ALTER TABLE pr_seen__new RENAME TO pr_seen;
+
+-- ── branch_chat_seen: UNIQUE (project_id, user_id, rfc_slug, branch) -> coll ─
+CREATE TABLE branch_chat_seen__new (
+    id                      INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id                 INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    rfc_slug                TEXT NOT NULL,
+    branch_name             TEXT NOT NULL,
+    last_seen_message_id    INTEGER REFERENCES thread_messages(id) ON DELETE SET NULL,
+    seen_at                 TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id           TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, user_id, rfc_slug, branch_name)
+);
+INSERT INTO branch_chat_seen__new
+    (id, user_id, rfc_slug, branch_name, last_seen_message_id, seen_at, collection_id)
+SELECT
+    s.id, s.user_id, s.rfc_slug, s.branch_name, s.last_seen_message_id, s.seen_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = s.project_id LIMIT 1)
+FROM branch_chat_seen s;
+DROP TABLE branch_chat_seen;
+ALTER TABLE branch_chat_seen__new RENAME TO branch_chat_seen;
+
+-- ── funder_consents: PRIMARY KEY (project_id, user_id, rfc_slug) -> collection
+CREATE TABLE funder_consents__new (
+    user_id     INTEGER NOT NULL,
+    rfc_slug    TEXT    NOT NULL,
+    created_at  TEXT    NOT NULL DEFAULT (datetime('now')),
+    collection_id  TEXT NOT NULL DEFAULT 'default',
+    PRIMARY KEY (collection_id, user_id, rfc_slug),
+    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
+);
+INSERT INTO funder_consents__new (user_id, rfc_slug, created_at, collection_id)
+SELECT f.user_id, f.rfc_slug, f.created_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = f.project_id LIMIT 1)
+FROM funder_consents f;
+DROP TABLE funder_consents;
+ALTER TABLE funder_consents__new RENAME TO funder_consents;
+CREATE INDEX idx_funder_consents_slug ON funder_consents (rfc_slug);
+
+-- ── rfc_collaborators: UNIQUE idx + composite FK -> collection_id ───────────
+CREATE TABLE rfc_collaborators__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug        TEXT NOT NULL,
+    user_id         INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role_in_rfc     TEXT NOT NULL CHECK (role_in_rfc IN ('contributor', 'discussant')),
+    invitation_id   INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id   TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (collection_id, rfc_slug) REFERENCES cached_rfcs(collection_id, slug) ON DELETE CASCADE
+);
+INSERT INTO rfc_collaborators__new
+    (id, rfc_slug, user_id, role_in_rfc, invitation_id, created_at, collection_id)
+SELECT
+    rc.id, rc.rfc_slug, rc.user_id, rc.role_in_rfc, rc.invitation_id, rc.created_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = rc.project_id LIMIT 1)
+FROM rfc_collaborators rc;
+DROP TABLE rfc_collaborators;
+ALTER TABLE rfc_collaborators__new RENAME TO rfc_collaborators;
+CREATE UNIQUE INDEX idx_rfc_collaborators_unique ON rfc_collaborators (collection_id, rfc_slug, user_id);
+CREATE INDEX idx_rfc_collaborators_user ON rfc_collaborators (user_id);
+
+-- ── contribution_requests: UNIQUE idx (pending) + composite FK -> collection ─
+CREATE TABLE contribution_requests__new (
+    id                  INTEGER PRIMARY KEY AUTOINCREMENT,
+    rfc_slug            TEXT NOT NULL,
+    requester_user_id   INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    matched_term        TEXT NOT NULL,
+    who_i_am            TEXT NOT NULL,
+    why                 TEXT NOT NULL,
+    use_case            TEXT,
+    status              TEXT NOT NULL DEFAULT 'pending'
+                            CHECK (status IN ('pending', 'accepted', 'declined')),
+    created_at          TEXT NOT NULL DEFAULT (datetime('now')),
+    decided_at          TEXT,
+    decided_by_user_id  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    invitation_id       INTEGER REFERENCES rfc_invitations(id) ON DELETE SET NULL,
+    notification_id     INTEGER REFERENCES notifications(id) ON DELETE SET NULL,
+    collection_id       TEXT NOT NULL DEFAULT 'default',
+    FOREIGN KEY (collection_id, rfc_slug) REFERENCES cached_rfcs(collection_id, slug) ON DELETE CASCADE
+);
+INSERT INTO contribution_requests__new
+    (id, rfc_slug, requester_user_id, matched_term, who_i_am, why, use_case, status,
+     created_at, decided_at, decided_by_user_id, invitation_id, notification_id, collection_id)
+SELECT
+    cr.id, cr.rfc_slug, cr.requester_user_id, cr.matched_term, cr.who_i_am, cr.why, cr.use_case, cr.status,
+    cr.created_at, cr.decided_at, cr.decided_by_user_id, cr.invitation_id, cr.notification_id,
+    (SELECT c.id FROM collections c WHERE c.project_id = cr.project_id LIMIT 1)
+FROM contribution_requests cr;
+DROP TABLE contribution_requests;
+ALTER TABLE contribution_requests__new RENAME TO contribution_requests;
+CREATE INDEX idx_contribution_requests_rfc ON contribution_requests(rfc_slug, status);
+CREATE INDEX idx_contribution_requests_requester ON contribution_requests(requester_user_id, status);
+CREATE UNIQUE INDEX idx_contribution_requests_one_open
+    ON contribution_requests(collection_id, rfc_slug, requester_user_id)
+    WHERE status = 'pending';
+
+-- ── proposed_use_cases: UNIQUE (project_id, scope, pr_number) -> collection ──
+CREATE TABLE proposed_use_cases__new (
+    id              INTEGER PRIMARY KEY AUTOINCREMENT,
+    scope           TEXT NOT NULL CHECK (scope IN ('rfc', 'pr')),
+    rfc_slug        TEXT NOT NULL,
+    pr_number       INTEGER NOT NULL,
+    use_case        TEXT NOT NULL,
+    created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+    collection_id   TEXT NOT NULL DEFAULT 'default',
+    UNIQUE (collection_id, scope, pr_number)
+);
+INSERT INTO proposed_use_cases__new
+    (id, scope, rfc_slug, pr_number, use_case, created_at, collection_id)
+SELECT
+    u.id, u.scope, u.rfc_slug, u.pr_number, u.use_case, u.created_at,
+    (SELECT c.id FROM collections c WHERE c.project_id = u.project_id LIMIT 1)
+FROM proposed_use_cases u;
+DROP TABLE proposed_use_cases;
+ALTER TABLE proposed_use_cases__new RENAME TO proposed_use_cases;
+CREATE INDEX idx_proposed_use_cases_lookup ON proposed_use_cases (scope, pr_number);
+CREATE INDEX idx_proposed_use_cases_slug ON proposed_use_cases (scope, rfc_slug);
+
+-- ── project_members -> memberships(scope_type, scope_id, …); roles collapsed ─
+CREATE TABLE memberships (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    scope_type  TEXT NOT NULL CHECK (scope_type IN ('project', 'collection')),
+    scope_id    TEXT NOT NULL,
+    user_id     INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role        TEXT NOT NULL CHECK (role IN ('owner', 'contributor')),
+    granted_by  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    granted_at  TEXT NOT NULL DEFAULT (datetime('now')),
+    UNIQUE (scope_type, scope_id, user_id)
+);
+CREATE INDEX idx_memberships_user ON memberships(user_id);
+CREATE INDEX idx_memberships_scope ON memberships(scope_type, scope_id);
+
+-- M2 project_members rows attached at what is now the *collection*; collapse the
+-- role enum (project_admin -> owner, project_contributor -> contributor;
+-- project_viewer dropped this pass, §B.3) and migrate onto the default
+-- collection of each project.
+INSERT INTO memberships (scope_type, scope_id, user_id, role, granted_by, granted_at)
+SELECT 'collection',
+       (SELECT c.id FROM collections c WHERE c.project_id = pm.project_id LIMIT 1),
+       pm.user_id,
+       CASE pm.role WHEN 'project_admin' THEN 'owner'
+                    WHEN 'project_contributor' THEN 'contributor'
+                    ELSE 'contributor' END,
+       pm.granted_by, pm.granted_at
+FROM project_members pm
+WHERE pm.role IN ('project_admin', 'project_contributor');
+DROP TABLE project_members;

backend/migrations/030_global_scope.sql

@@ -0,0 +1,34 @@
+-- migrate:no-foreign-keys
+--
+-- §22 three-tier — S3. Admit a *global*-scope grant to the memberships table.
+--
+-- §B.2's resolver folds four layers (global → project → collection → per-entry).
+-- Migration 029 created `memberships` with scope_type ∈ {project, collection}
+-- only; the global tier was left to S3. A global grant is how a "global RFC
+-- Contributor" (a contributor who may propose in every collection of every
+-- project, distinct from a deployment owner/admin) is represented — see
+-- docs/design/2026-06-05-three-tier-projects-collections.md §B.2/§B.3 and the
+-- C.1 "cleo" scenario.
+--
+-- SQLite can't ALTER a CHECK constraint in place, so the table is rebuilt by the
+-- create-copy-drop-rename procedure (the 028/029 pattern). The global scope uses
+-- a stable sentinel scope_id of '*' (one global tier per deployment); the
+-- UNIQUE(scope_type, scope_id, user_id) then admits exactly one global grant per
+-- user, mirroring the project/collection rows.
+
+CREATE TABLE memberships__new (
+    id          INTEGER PRIMARY KEY AUTOINCREMENT,
+    scope_type  TEXT NOT NULL CHECK (scope_type IN ('global', 'project', 'collection')),
+    scope_id    TEXT NOT NULL,
+    user_id     INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    role        TEXT NOT NULL CHECK (role IN ('owner', 'contributor')),
+    granted_by  INTEGER REFERENCES users(id) ON DELETE SET NULL,
+    granted_at  TEXT NOT NULL DEFAULT (datetime('now')),
+    UNIQUE (scope_type, scope_id, user_id)
+);
+INSERT INTO memberships__new (id, scope_type, scope_id, user_id, role, granted_by, granted_at)
+SELECT id, scope_type, scope_id, user_id, role, granted_by, granted_at FROM memberships;
+DROP TABLE memberships;
+ALTER TABLE memberships__new RENAME TO memberships;
+CREATE INDEX idx_memberships_user ON memberships(user_id);
+CREATE INDEX idx_memberships_scope ON memberships(scope_type, scope_id);

backend/tests/conftest.py

@@ -0,0 +1,19 @@
+"""Shared pytest fixtures for the backend suite.
+
+Added in v0.27.0 (security audit 0026) alongside the new per-IP rate
+limiter. The limiters in `app.ratelimit` are process-global singletons,
+so their state survives across tests within a run; without a reset, the
+accumulated requests from earlier tests exhaust the budget and later
+tests see spurious 429s. This autouse fixture gives every test a clean
+limiter window.
+"""
+import pytest
+
+from app import ratelimit
+
+
+@pytest.fixture(autouse=True)
+def _reset_rate_limiters():
+    ratelimit._reset_all_for_tests()
+    yield
+    ratelimit._reset_all_for_tests()

backend/tests/test_admin_create_user_invite_vertical.py

@@ -0,0 +1,728 @@
+"""End-to-end integration tests for v0.17.0's admin-create user +
+invite-email + claim-flow vertical (roadmap item #16, §6.1).
+
+The release lands three halves of the same surface:
+
+  * **Admin-create user** at `POST /api/admin/users`. The admin types
+    email, first/last name, role, and an optional custom message. The
+    framework provisions the invitee `users` row (granted, with the
+    chosen role) and writes a `user_invite_tokens` row carrying the
+    bcrypt-hashed opaque token. The "pending invite" discriminator is
+    the active `user_invite_tokens` row joined on `invited_user_id`,
+    not a NULL column on `users` (the existing `last_seen_at` column
+    is NOT NULL). An invite email dispatches via the existing SMTP
+    relay.
+
+  * **Pending-invite admin listing** at `GET /api/admin/users/invites`.
+    Lists active (not claimed, not expired) invites for the admin's
+    "I sent these but they haven't been claimed yet" view.
+
+  * **Claim** at `POST /api/invites/claim`. The invitee POSTs the token
+    they got via email; the framework verifies, marks the row claimed,
+    signs them in (skipping OTC on first sign-in per the roadmap), and
+    returns a `needs_passcode` hint for the frontend to route to the
+    passcode-set screen.
+
+The tests prove:
+
+  * The happy path: admin creates → invite row + email envelope land →
+    invitee claims with the token → session is established.
+  * Non-admin caller is refused 403.
+  * Self-invite is refused 422.
+  * Duplicate email is refused 409.
+  * Owner-grant by non-owner is refused 422.
+  * Malformed role is refused 422 (pydantic regex).
+  * Custom message over 500 chars is refused 422 (pydantic max_length).
+  * Claim with valid token: signs in + marks row claimed.
+  * Claim with expired token: HTTP 410.
+  * Claim with already-claimed token: HTTP 410.
+  * Claim with unknown token: HTTP 400.
+  * The admin-create gesture writes a `permission_events` row with
+    event_kind='user_invited'.
+  * The user listing surfaces the `pending_invite` field for invited-
+    but-not-yet-claimed users, and clears it after claim.
+"""
+from __future__ import annotations
+
+import json
+
+from test_propose_vertical import (  # noqa: F401 — fixtures land via import
+    FakeGitea,
+    app_with_fake_gitea,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+
+
+def _reset_outbound():
+    from app import email as email_mod
+    email_mod.reset_sent_envelopes()
+
+
+def _outbound_invite_envelopes(to_address: str | None = None) -> list[dict]:
+    """Pull the invite-kind envelopes off the shared notifier buffer.
+
+    Mirrors the OTC code-extraction helper in
+    test_admin_users_vertical.py — invite emails land in the same
+    `_SENT` buffer with `kind='invite'`.
+    """
+    from app import email as email_mod
+    out = []
+    for env in email_mod.sent_envelopes():
+        if env.get("kind") != "invite":
+            continue
+        if to_address is not None and env["to"] != to_address:
+            continue
+        out.append(env)
+    return out
+
+
+def _extract_claim_url(envelope: dict) -> str:
+    """Pull the claim URL out of the invite email body."""
+    for line in envelope["body"].splitlines():
+        line = line.strip()
+        if line.startswith("http") and "/invites/claim" in line:
+            return line
+    raise AssertionError(f"no claim URL in envelope body: {envelope['body']!r}")
+
+
+def _extract_claim_token(envelope: dict) -> str:
+    """Pull the `token` query-string param out of the claim URL."""
+    from urllib.parse import urlparse, parse_qs
+    url = _extract_claim_url(envelope)
+    qs = parse_qs(urlparse(url).query)
+    return qs["token"][0]
+
+
+# ---------------------------------------------------------------------------
+# Admin create + invite — happy path
+# ---------------------------------------------------------------------------
+
+
+def test_admin_create_user_invite_happy_path(app_with_fake_gitea):
+    """Admin creates → user row + invite-token row + email envelope all
+    land; the response carries the created ids and the inviter is the
+    admin who issued the gesture."""
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=100, login="adminzero", role="admin")
+        sign_in_as(
+            client, user_id=100, gitea_login="adminzero",
+            display_name="Admin Zero", role="admin",
+            email="adminzero@test",
+        )
+        _reset_outbound()
+
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "invitee@example.com",
+                "first_name": "Inv",
+                "last_name": "Tee",
+                "role": "contributor",
+                "custom_message": "We chatted at the conference — welcome!",
+            },
+        )
+        assert r.status_code == 200, r.text
+        body = r.json()
+        assert body["ok"] is True
+        assert body["email"] == "invitee@example.com"
+        assert body["role"] == "contributor"
+        assert body["invite_id"] > 0
+        assert body["invited_user_id"] > 0
+
+        # User row exists with the chosen role + granted. The "pending
+        # invite" discriminator is the active `user_invite_tokens` row,
+        # not a NULL column on `users` — see the invites.create_invite
+        # docstring for the reasoning.
+        row = db.conn().execute(
+            "SELECT role, permission_state, first_name, last_name "
+            "FROM users WHERE email = ? COLLATE NOCASE",
+            ("invitee@example.com",),
+        ).fetchone()
+        assert row is not None
+        assert row["role"] == "contributor"
+        assert row["permission_state"] == "granted"
+        assert row["first_name"] == "Inv"
+        assert row["last_name"] == "Tee"
+
+        # Invite-token row exists with the matching ids and the custom
+        # message persisted verbatim.
+        invite = db.conn().execute(
+            "SELECT email, role, custom_message, created_by_admin_id, "
+            "invited_user_id, claimed_at FROM user_invite_tokens WHERE id = ?",
+            (body["invite_id"],),
+        ).fetchone()
+        assert invite is not None
+        assert invite["email"] == "invitee@example.com"
+        assert invite["role"] == "contributor"
+        assert invite["custom_message"] == "We chatted at the conference — welcome!"
+        assert invite["created_by_admin_id"] == 100
+        assert invite["invited_user_id"] == body["invited_user_id"]
+        assert invite["claimed_at"] is None
+
+        # Email envelope landed with the invite kind and embeds the
+        # custom message + claim URL. The inviter display name comes
+        # off the DB row (which provision_user_row sets to
+        # login.capitalize()), not the sign_in_as cookie payload.
+        envelopes = _outbound_invite_envelopes(to_address="invitee@example.com")
+        assert len(envelopes) == 1
+        env = envelopes[0]
+        assert "Adminzero" in env["subject"] or "Adminzero" in env["body"]
+        assert "We chatted at the conference — welcome!" in env["body"]
+        # Claim URL is well-formed.
+        url = _extract_claim_url(env)
+        assert "/invites/claim?token=" in url
+
+        # `permission_events` row landed with event_kind='user_invited'.
+        ev = db.conn().execute(
+            "SELECT actor_user_id, subject_user_id, event_kind, details "
+            "FROM permission_events WHERE event_kind = 'user_invited'"
+        ).fetchall()
+        assert len(ev) == 1
+        assert ev[0]["actor_user_id"] == 100
+        assert ev[0]["subject_user_id"] == body["invited_user_id"]
+        details = json.loads(ev[0]["details"])
+        assert details["email"] == "invitee@example.com"
+        assert details["role"] == "contributor"
+
+
+# ---------------------------------------------------------------------------
+# Refusals on the admin-create endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_admin_create_user_invite_refuses_non_admin(app_with_fake_gitea):
+    """A contributor caller is refused 403; an anonymous caller 401."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=110, login="contrib", role="contributor")
+        sign_in_as(
+            client, user_id=110, gitea_login="contrib",
+            display_name="Contrib", role="contributor",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={"email": "x@y.com", "role": "contributor"},
+        )
+        assert r.status_code == 403, r.text
+
+        client.cookies.clear()
+        r = client.post(
+            "/api/admin/users",
+            json={"email": "x@y.com", "role": "contributor"},
+        )
+        assert r.status_code == 401
+
+
+def test_admin_create_user_invite_refuses_self_email(app_with_fake_gitea):
+    """An admin trying to invite their own email is refused 422 —
+    self-invite is the wrong channel; the role-change endpoint exists
+    for self-edits."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=120, login="adm", role="admin")
+        # Manually set the admin's email since provision_user_row's
+        # fixture uses login@test; this is what we'll try to self-invite.
+        from app import db
+        db.conn().execute(
+            "UPDATE users SET email = ? WHERE id = ?",
+            ("selfinviter@example.com", 120),
+        )
+        sign_in_as(
+            client, user_id=120, gitea_login="adm",
+            display_name="Adm", role="admin",
+            email="selfinviter@example.com",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "selfinviter@example.com",
+                "role": "contributor",
+            },
+        )
+        assert r.status_code == 422, r.text
+        assert "yourself" in r.json()["detail"].lower()
+
+
+def test_admin_create_user_invite_refuses_duplicate_email(app_with_fake_gitea):
+    """An admin trying to invite an email that already maps to a users
+    row is refused 409 — the existing role / grant gestures are the
+    right surface for an existing user."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=130, login="adminD", role="admin")
+        provision_user_row(user_id=131, login="existingone", role="contributor")
+        sign_in_as(
+            client, user_id=130, gitea_login="adminD",
+            display_name="Admin D", role="admin",
+        )
+        # provision_user_row sets email to <login>@test, so:
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "existingone@test",
+                "role": "contributor",
+            },
+        )
+        assert r.status_code == 409, r.text
+
+
+def test_admin_create_user_invite_owner_grant_refused_for_non_owner(app_with_fake_gitea):
+    """An admin (not owner) trying to invite a fresh user as `owner` is
+    refused 422 — §6.1's owner-zero is the only bootstrap path."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=140, login="adminNoOwner", role="admin")
+        sign_in_as(
+            client, user_id=140, gitea_login="adminNoOwner",
+            display_name="Admin", role="admin",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "wouldbeowner@example.com",
+                "role": "owner",
+            },
+        )
+        assert r.status_code == 422, r.text
+
+
+def test_admin_create_user_invite_owner_can_invite_as_owner(app_with_fake_gitea):
+    """A sitting owner can invite a fresh user as `owner` — the §6.1
+    role-grant channel. Sanity check that the owner-grant path itself
+    works, paired with the refusal above."""
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=150, login="ownerzero", role="owner")
+        sign_in_as(
+            client, user_id=150, gitea_login="ownerzero",
+            display_name="Owner Zero", role="owner",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "newowner@example.com",
+                "role": "owner",
+            },
+        )
+        assert r.status_code == 200, r.text
+        row = db.conn().execute(
+            "SELECT role FROM users WHERE email = ? COLLATE NOCASE",
+            ("newowner@example.com",),
+        ).fetchone()
+        assert row["role"] == "owner"
+
+
+def test_admin_create_user_invite_refuses_malformed_role(app_with_fake_gitea):
+    """The pydantic regex refuses any role outside the §6.1 set."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=160, login="adminR", role="admin")
+        sign_in_as(
+            client, user_id=160, gitea_login="adminR",
+            display_name="Admin R", role="admin",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "ok@example.com",
+                "role": "superuser",
+            },
+        )
+        assert r.status_code == 422
+
+
+def test_admin_create_user_invite_refuses_long_custom_message(app_with_fake_gitea):
+    """Custom message over the 500-char ceiling is refused 422."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=170, login="adminM", role="admin")
+        sign_in_as(
+            client, user_id=170, gitea_login="adminM",
+            display_name="Admin M", role="admin",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "ok@example.com",
+                "role": "contributor",
+                "custom_message": "x" * 501,
+            },
+        )
+        assert r.status_code == 422
+
+
+# ---------------------------------------------------------------------------
+# Claim flow
+# ---------------------------------------------------------------------------
+
+
+def test_claim_with_valid_token_signs_in_and_marks_claimed(app_with_fake_gitea):
+    """End-to-end: admin creates → invitee posts the token to
+    /api/invites/claim → session lands + row marked claimed +
+    last_seen_at stamps on the user row (the pending-invite
+    discriminator clears)."""
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=200, login="adminC", role="admin")
+        sign_in_as(
+            client, user_id=200, gitea_login="adminC",
+            display_name="Admin C", role="admin",
+        )
+        _reset_outbound()
+
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "claimant@example.com",
+                "first_name": "Clai",
+                "last_name": "Mant",
+                "role": "contributor",
+            },
+        )
+        assert r.status_code == 200
+        invite_id = r.json()["invite_id"]
+        invited_user_id = r.json()["invited_user_id"]
+
+        env = _outbound_invite_envelopes("claimant@example.com")[0]
+        token = _extract_claim_token(env)
+
+        # The invitee's request is anonymous (they have no session
+        # yet). We clear the admin's session cookie to simulate this.
+        client.cookies.clear()
+
+        r = client.post(
+            "/api/invites/claim",
+            json={"token": token},
+        )
+        assert r.status_code == 200, r.text
+        body = r.json()
+        assert body["ok"] is True
+        assert body["user"]["id"] == invited_user_id
+        assert body["user"]["role"] == "contributor"
+        assert body["user"]["permission_state"] == "granted"
+        # The user has no passcode set yet → frontend should route to
+        # passcode-set per the roadmap.
+        assert body["needs_passcode"] is True
+
+        # Row marked claimed; last_seen_at populated.
+        invite = db.conn().execute(
+            "SELECT claimed_at, claimed_by_user_id FROM user_invite_tokens "
+            "WHERE id = ?",
+            (invite_id,),
+        ).fetchone()
+        assert invite["claimed_at"] is not None
+        assert invite["claimed_by_user_id"] == invited_user_id
+
+        user_row = db.conn().execute(
+            "SELECT last_seen_at FROM users WHERE id = ?",
+            (invited_user_id,),
+        ).fetchone()
+        assert user_row["last_seen_at"] is not None
+
+
+def test_claim_with_expired_token_returns_410(app_with_fake_gitea):
+    """A token whose `expires_at` has passed surfaces as HTTP 410."""
+    from fastapi.testclient import TestClient
+    from app import db, invites
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=210, login="adminE", role="admin")
+        sign_in_as(
+            client, user_id=210, gitea_login="adminE",
+            display_name="Admin E", role="admin",
+        )
+        _reset_outbound()
+
+        # Create the invite, then back-date the expires_at to the past.
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "expired@example.com",
+                "role": "contributor",
+            },
+        )
+        assert r.status_code == 200
+        invite_id = r.json()["invite_id"]
+        db.conn().execute(
+            "UPDATE user_invite_tokens SET expires_at = datetime('now', '-1 day') "
+            "WHERE id = ?",
+            (invite_id,),
+        )
+        env = _outbound_invite_envelopes("expired@example.com")[0]
+        token = _extract_claim_token(env)
+
+        client.cookies.clear()
+        r = client.post("/api/invites/claim", json={"token": token})
+        assert r.status_code == 410, r.text
+        assert "expired" in r.json()["detail"].lower()
+
+
+def test_claim_with_already_claimed_token_returns_410(app_with_fake_gitea):
+    """Re-claiming an already-consumed token surfaces as HTTP 410."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=220, login="adminA", role="admin")
+        sign_in_as(
+            client, user_id=220, gitea_login="adminA",
+            display_name="Admin A", role="admin",
+        )
+        _reset_outbound()
+
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "twice@example.com",
+                "role": "contributor",
+            },
+        )
+        assert r.status_code == 200
+        env = _outbound_invite_envelopes("twice@example.com")[0]
+        token = _extract_claim_token(env)
+
+        client.cookies.clear()
+        # First claim succeeds.
+        r = client.post("/api/invites/claim", json={"token": token})
+        assert r.status_code == 200
+        # Second claim, with the same token, refuses with 410.
+        client.cookies.clear()
+        r = client.post("/api/invites/claim", json={"token": token})
+        assert r.status_code == 410, r.text
+        assert "already" in r.json()["detail"].lower()
+
+
+def test_claim_with_unknown_token_returns_400(app_with_fake_gitea):
+    """A token that doesn't match any active invite is HTTP 400."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        # No invite ever created; the token is whatever the attacker
+        # types in. The endpoint should refuse without disclosing
+        # whether the token "looked" right.
+        r = client.post(
+            "/api/invites/claim",
+            json={"token": "totally-made-up-token-string-that-is-not-real"},
+        )
+        assert r.status_code == 400, r.text
+
+
+# ---------------------------------------------------------------------------
+# Pending-invite admin listing
+# ---------------------------------------------------------------------------
+
+
+def test_pending_invites_listing_shows_active_invites_only(app_with_fake_gitea):
+    """The `GET /api/admin/users/invites` listing filters to active
+    invites — claimed and expired rows do not surface here (the admin
+    user-listing carries the per-row pending-invite badge for the
+    living rows; once claimed, the badge clears)."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=300, login="adminL", role="admin")
+        sign_in_as(
+            client, user_id=300, gitea_login="adminL",
+            display_name="Admin L", role="admin",
+        )
+        _reset_outbound()
+
+        # Create three invites: one stays pending, one we'll claim, one
+        # we'll back-date to expired.
+        for email in ("alive@ex.co", "claimed@ex.co", "expired@ex.co"):
+            r = client.post(
+                "/api/admin/users",
+                json={"email": email, "role": "contributor"},
+            )
+            assert r.status_code == 200
+
+        # Claim the middle one.
+        env = _outbound_invite_envelopes("claimed@ex.co")[0]
+        token_claim = _extract_claim_token(env)
+
+        # Expire the third one.
+        from app import db
+        db.conn().execute(
+            "UPDATE user_invite_tokens SET expires_at = datetime('now', '-1 day') "
+            "WHERE email = 'expired@ex.co'"
+        )
+
+        # The admin's session is still on the cookie. Claim works
+        # anonymously; we clear and restore.
+        admin_cookie = client.cookies.get("rfc_session")
+        client.cookies.clear()
+        r = client.post("/api/invites/claim", json={"token": token_claim})
+        assert r.status_code == 200
+        client.cookies.set("rfc_session", admin_cookie)
+
+        r = client.get("/api/admin/users/invites")
+        assert r.status_code == 200, r.text
+        items = r.json()["items"]
+        emails = sorted(i["email"] for i in items)
+        assert emails == ["alive@ex.co"]
+
+
+def test_pending_invite_badge_clears_after_claim(app_with_fake_gitea):
+    """The `/api/admin/users` listing surfaces `pending_invite` while
+    the invite is unclaimed; after the invitee claims, the row's
+    pending_invite is null."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=310, login="adminB", role="admin")
+        sign_in_as(
+            client, user_id=310, gitea_login="adminB",
+            display_name="Admin B", role="admin",
+        )
+        _reset_outbound()
+
+        r = client.post(
+            "/api/admin/users",
+            json={"email": "badgey@ex.co", "role": "contributor"},
+        )
+        assert r.status_code == 200
+        invited_id = r.json()["invited_user_id"]
+
+        # Before claim — pending_invite is populated.
+        r = client.get("/api/admin/users")
+        assert r.status_code == 200
+        row = next(u for u in r.json()["items"] if u["id"] == invited_id)
+        assert row["pending_invite"] is not None
+        assert row["pending_invite"]["invite_id"] > 0
+
+        # Claim.
+        env = _outbound_invite_envelopes("badgey@ex.co")[0]
+        token = _extract_claim_token(env)
+        admin_cookie = client.cookies.get("rfc_session")
+        client.cookies.clear()
+        r = client.post("/api/invites/claim", json={"token": token})
+        assert r.status_code == 200
+        client.cookies.set("rfc_session", admin_cookie)
+
+        # After claim — pending_invite is null.
+        r = client.get("/api/admin/users")
+        assert r.status_code == 200
+        row = next(u for u in r.json()["items"] if u["id"] == invited_id)
+        assert row["pending_invite"] is None
+
+
+def test_pending_invites_listing_admin_only(app_with_fake_gitea):
+    """The listing requires admin/owner; contributor gets 403."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=320, login="contribL", role="contributor")
+        sign_in_as(
+            client, user_id=320, gitea_login="contribL",
+            display_name="Contrib L", role="contributor",
+        )
+        r = client.get("/api/admin/users/invites")
+        assert r.status_code == 403
+
+
+# ---------------------------------------------------------------------------
+# v0.18.0: invite-envelope header shape — Slice 2
+#
+# Invite mail goes through `build_envelope` and MUST land Date,
+# Message-ID, Auto-Submitted, AND a `List-Unsubscribe: <mailto:…>`
+# (no URL — the invitee isn't a user yet, so no per-user opt-out
+# row exists). The mailto: target is the operator's `EMAIL_FROM`
+# by default; the operator can override via `EMAIL_UNSUBSCRIBE_MAILTO`.
+# ---------------------------------------------------------------------------
+
+
+def _provision_admin_and_send_invite(client, app_with_fake_gitea_fixture, *, to: str = "headers@ex.co"):
+    provision_user_row(user_id=400, login="adminH", role="admin")
+    sign_in_as(
+        client, user_id=400, gitea_login="adminH",
+        display_name="Admin H", role="admin",
+        email="adminh@test",
+    )
+    _reset_outbound()
+    r = client.post(
+        "/api/admin/users",
+        json={
+            "email": to,
+            "first_name": "Header",
+            "last_name": "Test",
+            "role": "contributor",
+            "custom_message": "",
+        },
+    )
+    assert r.status_code == 200, r.text
+    return _outbound_invite_envelopes(to)[-1]
+
+
+def test_invite_envelope_sets_date_messageid_autosubmitted(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from email.utils import parsedate_to_datetime
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        env = _provision_admin_and_send_invite(client, (app, _fake))
+        msg = env["message"]
+        assert parsedate_to_datetime(msg["Date"]) is not None
+        assert msg["Message-ID"].startswith("<") and msg["Message-ID"].endswith(">")
+        assert msg["Auto-Submitted"] == "auto-generated"
+
+
+def test_invite_envelope_has_mailto_list_unsubscribe_only(app_with_fake_gitea):
+    """The invitee isn't a user yet — no per-user opt-out URL is
+    available. The `List-Unsubscribe` MUST be a mailto: form, and
+    the `List-Unsubscribe-Post` header MUST be absent (the
+    one-click semantic requires a URL the MUA can POST to)."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        env = _provision_admin_and_send_invite(client, (app, _fake))
+        msg = env["message"]
+        lu = msg["List-Unsubscribe"]
+        assert lu is not None and lu.startswith("<mailto:")
+        # No URL part — invite is mailto-only.
+        assert "https://" not in lu and "http://" not in lu
+        assert msg["List-Unsubscribe-Post"] is None
+
+
+def test_invite_envelope_respects_email_unsubscribe_mailto_override(app_with_fake_gitea, monkeypatch):
+    """When `EMAIL_UNSUBSCRIBE_MAILTO` is set, the mailto: target on
+    `List-Unsubscribe` honors it (lets a deployment route opt-outs
+    to a humans-monitored mailbox distinct from the no-reply
+    sender)."""
+    from fastapi.testclient import TestClient
+
+    monkeypatch.setenv("EMAIL_UNSUBSCRIBE_MAILTO", "ohm@wiggleverse.org?subject=remove")
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        env = _provision_admin_and_send_invite(client, (app, _fake))
+        msg = env["message"]
+        assert "ohm@wiggleverse.org?subject=remove" in msg["List-Unsubscribe"]

backend/tests/test_api_deployment.py

@@ -0,0 +1,139 @@
+"""§22.9/§22.5 — GET /api/deployment + GET /api/projects/:id with visibility."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _add_project(pid, name, vis, typ="document"):
+    # §22 three-tier: a project (grouping tier) + its default collection (the
+    # per-corpus type/initial_state moved down in migration 029). The default
+    # collection keys by the project id so it is globally unique in tests.
+    from app import db
+    db.conn().execute(
+        "INSERT OR REPLACE INTO projects (id, name, content_repo, visibility) VALUES (?, ?, ?, ?)",
+        (pid, name, pid, vis),
+    )
+    db.conn().execute(
+        "INSERT OR REPLACE INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES (?, ?, ?, '', 'super-draft', ?, ?)",
+        (pid, pid, typ, vis, name),
+    )
+
+
+def test_deployment_lists_public_omits_gated_and_unlisted_for_anon(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("pub", "Public", "public")
+        _add_project("gat", "Gated", "gated")
+        _add_project("unl", "Unlisted", "unlisted")
+        r = client.get("/api/deployment")
+        assert r.status_code == 200
+        body = r.json()
+        assert body["name"] == "Test Deployment"
+        ids = {p["id"] for p in body["projects"]}
+        assert "pub" in ids and "default" in ids  # both public
+        assert "gat" not in ids                    # gated, anon not a member
+        assert "unl" not in ids                    # unlisted never enumerated
+
+
+def test_projects_id_404_for_gated_non_member(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("gat", "Gated", "gated")
+        assert client.get("/api/projects/gat").status_code == 404
+
+
+def test_projects_id_returns_config_for_public(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        from app import db
+        db.conn().execute(
+            "UPDATE projects SET config_json = ? WHERE id = 'default'",
+            ('{"theme": {"accent": "#5b5bd6"}}',),
+        )
+        r = client.get("/api/projects/default")
+        assert r.status_code == 200
+        body = r.json()
+        assert body["id"] == "default"
+        assert body["type"] == "document"
+        assert body["visibility"] == "public"
+        assert body["theme"] == {"accent": "#5b5bd6"}
+
+
+def test_projects_id_unlisted_readable_by_direct_id(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("unl", "Unlisted", "unlisted")
+        assert client.get("/api/projects/unl").status_code == 200
+
+
+def test_projects_id_unknown_returns_404_even_for_superuser(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner")
+        assert client.get("/api/projects/does-not-exist").status_code == 404
+
+
+def test_projects_id_unknown_returns_404_for_anon(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        assert client.get("/api/projects/nope").status_code == 404
+
+
+def test_deployment_includes_default_project_id(app_with_fake_gitea):
+    # §22.10 / M3-frontend guard contract: the frontend learns which project
+    # is the corpus-served (default) one from the deployment payload.
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        body = client.get("/api/deployment").json()
+        assert body["default_project_id"] == "default"
+
+
+def test_rfc_root_url_redirects_308_to_project_scoped(app_with_fake_gitea):
+    # §22.10 / §5: old corpus-root /rfc/<slug> → 308 /p/<default>/e/<slug>.
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.get("/rfc/human", follow_redirects=False)
+        assert r.status_code == 308
+        assert r.headers["location"] == "/p/default/c/default/e/human"
+
+
+def test_rfc_pr_url_redirects_308_to_project_scoped(app_with_fake_gitea):
+    # The old per-RFC PR deep link is preserved too.
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.get("/rfc/human/pr/7", follow_redirects=False)
+        assert r.status_code == 308
+        assert r.headers["location"] == "/p/default/c/default/e/human/pr/7"
+
+
+def test_proposals_root_url_redirects_308_to_project_scoped(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.get("/proposals/42", follow_redirects=False)
+        assert r.status_code == 308
+        assert r.headers["location"] == "/p/default/c/default/proposals/42"
+
+
+def test_gated_project_visible_and_readable_to_member(app_with_fake_gitea):
+    from app import db
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("teamx", "Team X", "gated")
+        provision_user_row(user_id=5, login="mia", role="contributor")
+        db.conn().execute(
+            "INSERT INTO memberships (scope_type, scope_id, user_id, role) VALUES ('collection', 'teamx', 5, 'contributor')"
+        )
+        sign_in_as(client, user_id=5, gitea_login="mia", display_name="Mia", role="contributor")
+        # member sees the gated project in the deployment directory
+        ids = {p["id"] for p in client.get("/api/deployment").json()["projects"]}
+        assert "teamx" in ids
+        # member can read it directly
+        r = client.get("/api/projects/teamx")
+        assert r.status_code == 200
+        assert r.json()["id"] == "teamx"

backend/tests/test_cache_review_fields.py

@@ -0,0 +1,24 @@
+"""§22.4c — _upsert_cached_rfc mirrors the review fields into cached_rfcs."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import app_with_fake_gitea, tmp_env  # noqa: F401
+
+
+def test_upsert_writes_review_fields(app_with_fake_gitea):
+    from app import cache, db, entry as entry_mod
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        e = entry_mod.Entry(
+            slug="rev", title="Rev", state="active",
+            unreviewed=True, reviewed_at="2026-06-03", reviewed_by="ben",
+        )
+        cache._upsert_cached_rfc(e, body_sha="sha-rev")
+        row = db.conn().execute(
+            "SELECT unreviewed, reviewed_at, reviewed_by FROM cached_rfcs WHERE slug = 'rev'"
+        ).fetchone()
+        assert row["unreviewed"] == 1
+        assert row["reviewed_at"] == "2026-06-03"
+        assert row["reviewed_by"] == "ben"

backend/tests/test_collection_create_vertical.py

@@ -0,0 +1,83 @@
+"""§22 S2 — create-collection vertical: a deployment owner/admin POSTs, the bot
+commits a `.collection.yaml`, and the registry mirror upserts the collections
+row (registry stays the source of truth)."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from app import db
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def test_create_collection_commits_manifest_and_mirrors(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben",
+                   role="owner", email="ben@test")
+        r = client.post("/api/projects/default/collections",
+                        json={"collection_id": "features", "type": "bdd", "name": "Features"})
+        assert r.status_code == 200, r.text
+        assert r.json()["type"] == "bdd"
+
+        # The bot committed the manifest to the content repo's main.
+        f = fake.files.get(("wiggleverse", "meta", "main", "features/.collection.yaml"))
+        assert f is not None
+        assert "type: bdd" in f["content"]
+
+        # The registry refresh mirrored it into a collections row.
+        row = db.conn().execute(
+            "SELECT type, project_id, subfolder FROM collections WHERE id='features'"
+        ).fetchone()
+        assert (row["type"], row["project_id"], row["subfolder"]) == ("bdd", "default", "features")
+
+        # It is now navigable via the directory + scoped serve.
+        items = client.get("/api/projects/default/collections").json()["items"]
+        assert any(c["id"] == "features" for c in items)
+        assert client.get("/api/projects/default/collections/features/rfcs").status_code == 200
+
+
+def test_create_collection_requires_admin(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        r = client.post("/api/projects/default/collections",
+                        json={"collection_id": "x", "type": "bdd"})
+        assert r.status_code in (401, 403)
+
+
+def test_create_collection_anonymous_rejected(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.post("/api/projects/default/collections",
+                        json={"collection_id": "x", "type": "bdd"})
+        assert r.status_code in (401, 403)
+
+
+def test_create_collection_rejects_duplicate(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben",
+                   role="owner", email="ben@test")
+        ok = client.post("/api/projects/default/collections",
+                         json={"collection_id": "features", "type": "bdd"})
+        assert ok.status_code == 200, ok.text
+        dup = client.post("/api/projects/default/collections",
+                          json={"collection_id": "features", "type": "bdd"})
+        assert dup.status_code == 409
+
+
+def test_create_collection_rejects_reserved_default_id(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben",
+                   role="owner", email="ben@test")
+        r = client.post("/api/projects/default/collections",
+                        json={"collection_id": "default", "type": "bdd"})
+        assert r.status_code == 422

backend/tests/test_collection_helpers.py

@@ -0,0 +1,64 @@
+"""§22 S2 — collection read helpers: list_collections / get_collection /
+subfolder_of."""
+from __future__ import annotations
+
+import tempfile
+from pathlib import Path
+
+from app import collections as collections_mod, db
+from app.config import Config
+
+
+def _db() -> Config:
+    cfg = Config(
+        gitea_url="x", gitea_bot_user="x", gitea_bot_token="x", gitea_org="x",
+        registry_repo="registry", oauth_client_id="x",
+        oauth_client_secret="x", app_url="x", secret_key="x",
+        database_path=Path(tempfile.mkdtemp(prefix="colhelp-")) / "t.db",
+        owner_gitea_login="x", webhook_secret="x",
+    )
+    db.run_migrations(cfg)
+    if db._CONN is not None:
+        db._CONN.close()
+        db._CONN = None
+    db.init(cfg)
+    return cfg
+
+
+def _seed(project_id="ohm"):
+    db.conn().execute(
+        "INSERT OR REPLACE INTO projects (id, name, content_repo, visibility, updated_at) "
+        "VALUES (?, 'Ohm', 'ohm-rfc', 'public', datetime('now'))", (project_id,))
+    for cid, sub, vis, name in [
+        ("default", "", "public", "Model"),
+        ("features", "features", "public", "Features"),
+        ("secret", "secret", "unlisted", "Secret"),
+    ]:
+        db.conn().execute(
+            "INSERT OR REPLACE INTO collections (id, project_id, type, subfolder, initial_state, "
+            "visibility, name, created_at, updated_at) VALUES (?,?, 'document', ?, "
+            "'super-draft', ?, ?, datetime('now'), datetime('now'))",
+            (cid, project_id, sub, vis, name))
+
+
+def test_list_collections_excludes_unlisted():
+    _db()
+    _seed()
+    ids = [c["id"] for c in collections_mod.list_collections("ohm", include_unlisted=False)]
+    assert ids == ["default", "features"]  # default first, then by name; 'secret' omitted
+
+
+def test_list_collections_include_unlisted():
+    _db()
+    _seed()
+    ids = {c["id"] for c in collections_mod.list_collections("ohm", include_unlisted=True)}
+    assert ids == {"default", "features", "secret"}
+
+
+def test_get_collection_and_subfolder():
+    _db()
+    _seed()
+    assert collections_mod.get_collection("features")["name"] == "Features"
+    assert collections_mod.subfolder_of("features") == "features"
+    assert collections_mod.subfolder_of("default") == ""
+    assert collections_mod.get_collection("nope") is None

backend/tests/test_collection_registry.py

@@ -0,0 +1,146 @@
+"""§22 S2 — the registry mirror reads `.collection.yaml` manifests inside each
+project's content repo and upserts a named collection per manifest. The default
+collection still flows from projects.yaml (test_registry.py)."""
+from __future__ import annotations
+
+import asyncio
+import base64
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from app import db, registry
+from app.config import Config
+
+
+def _db() -> Config:
+    cfg = Config(
+        gitea_url="x", gitea_bot_user="x", gitea_bot_token="x", gitea_org="wiggleverse",
+        registry_repo="registry", oauth_client_id="x",
+        oauth_client_secret="x", app_url="x", secret_key="x",
+        database_path=Path(tempfile.mkdtemp(prefix="colreg-")) / "t.db",
+        owner_gitea_login="x", webhook_secret="x",
+    )
+    db.run_migrations(cfg)
+    if db._CONN is not None:
+        db._CONN.close()
+        db._CONN = None
+    db.init(cfg)
+    return cfg
+
+
+# --- pure parser --------------------------------------------------------------
+
+
+def test_parse_collection_manifest_minimal():
+    doc = registry.parse_collection_manifest("type: bdd\n")
+    assert doc.type == "bdd"
+    # §22.4b: bdd defaults to 'active'; visibility inherits (None == inherit).
+    assert doc.initial_state == "active"
+    assert doc.visibility is None
+    assert doc.name is None
+
+
+def test_parse_collection_manifest_full():
+    doc = registry.parse_collection_manifest(
+        "type: document\nvisibility: public\ninitial_state: active\nname: Model\n"
+    )
+    assert (doc.type, doc.visibility, doc.initial_state, doc.name) == (
+        "document", "public", "active", "Model",
+    )
+
+
+def test_parse_collection_manifest_rejects_bad_type():
+    with pytest.raises(registry.RegistryError):
+        registry.parse_collection_manifest("type: nonsense\n")
+
+
+def test_parse_collection_manifest_rejects_bad_visibility():
+    with pytest.raises(registry.RegistryError):
+        registry.parse_collection_manifest("type: bdd\nvisibility: nope\n")
+
+
+# --- mirror discovery ---------------------------------------------------------
+
+
+class _FakeGitea:
+    """Minimal Gitea stub: projects.yaml in the registry repo + a content repo
+    whose root holds a `features/` subdir carrying a `.collection.yaml`."""
+
+    def __init__(self, projects_yaml: str, repo_tree: dict[str, dict[str, str]]):
+        self._projects_yaml = projects_yaml
+        self._repo_tree = repo_tree  # {repo: {path: text}}
+
+    async def get_contents(self, org, repo, path, ref="main"):
+        if path == "projects.yaml":
+            return {"type": "file",
+                    "content": base64.b64encode(self._projects_yaml.encode()).decode(),
+                    "sha": "regsha-test"}
+        text = self._repo_tree.get(repo, {}).get(path)
+        if text is None:
+            return None
+        return {"type": "file",
+                "content": base64.b64encode(text.encode()).decode(), "sha": "c0ffee"}
+
+    async def list_dir(self, org, repo, path, ref="main"):
+        # Root listing: surface each top-level segment as a 'dir' entry.
+        prefix = (path.rstrip("/") + "/") if path else ""
+        dirs = set()
+        for p in self._repo_tree.get(repo, {}):
+            if not p.startswith(prefix):
+                continue
+            rest = p[len(prefix):]
+            if "/" in rest:
+                dirs.add(rest.split("/", 1)[0])
+        return [{"type": "dir", "name": n, "path": prefix + n} for n in sorted(dirs)]
+
+
+_PROJECTS = (
+    "deployment:\n  name: Ohm\n  tagline: t\n"
+    "projects:\n  - id: ohm\n    name: Ohm\n    type: document\n"
+    "    content_repo: ohm-rfc\n    visibility: public\n"
+)
+
+
+def test_refresh_registry_mirrors_named_collection():
+    cfg = _db()
+    gitea = _FakeGitea(
+        projects_yaml=_PROJECTS,
+        repo_tree={"ohm-rfc": {"features/.collection.yaml": "type: bdd\nname: Features\n"}},
+    )
+    asyncio.run(registry.refresh_registry(cfg, gitea))
+    row = db.conn().execute(
+        "SELECT type, subfolder, name, project_id, visibility FROM collections WHERE id='features'"
+    ).fetchone()
+    assert row is not None
+    assert (row["type"], row["subfolder"], row["project_id"]) == ("bdd", "features", "ohm")
+    assert row["name"] == "Features"
+    # visibility inherits the project's (public) when the manifest omits it.
+    assert row["visibility"] == "public"
+
+
+def test_refresh_registry_leaves_default_collection_intact():
+    cfg = _db()
+    gitea = _FakeGitea(
+        projects_yaml=_PROJECTS,
+        repo_tree={"ohm-rfc": {"features/.collection.yaml": "type: bdd\n"}},
+    )
+    asyncio.run(registry.refresh_registry(cfg, gitea))
+    # The default collection (from projects.yaml) and the named one coexist.
+    ids = {r["id"] for r in db.conn().execute("SELECT id FROM collections")}
+    assert {"default", "features"} <= ids
+
+
+def test_refresh_registry_immutable_type_on_named_collection():
+    cfg = _db()
+    gitea = _FakeGitea(
+        projects_yaml=_PROJECTS,
+        repo_tree={"ohm-rfc": {"features/.collection.yaml": "type: bdd\n"}},
+    )
+    asyncio.run(registry.refresh_registry(cfg, gitea))
+    # A later manifest that flips the type is refused (§22.4a immutable type).
+    gitea._repo_tree["ohm-rfc"]["features/.collection.yaml"] = "type: document\n"
+    asyncio.run(registry.refresh_registry(cfg, gitea))
+    t = db.conn().execute("SELECT type FROM collections WHERE id='features'").fetchone()["type"]
+    assert t == "bdd"

backend/tests/test_collection_scoped_serve.py

@@ -0,0 +1,164 @@
+"""§22 S2 — collection-grained corpus mirror + collection-scoped serve/propose.
+
+The mirror test drives cache.refresh_meta_repo against an in-memory content repo
+holding entries under both the default `rfcs/` and a named collection's
+`features/rfcs/`, and asserts cached_rfcs is keyed by the right collection_id."""
+from __future__ import annotations
+
+import asyncio
+import tempfile
+from pathlib import Path
+
+from app import cache, db
+from app.config import Config
+
+
+def _db() -> Config:
+    cfg = Config(
+        gitea_url="x", gitea_bot_user="x", gitea_bot_token="x", gitea_org="wiggleverse",
+        registry_repo="registry", oauth_client_id="x",
+        oauth_client_secret="x", app_url="x", secret_key="x",
+        database_path=Path(tempfile.mkdtemp(prefix="colserve-")) / "t.db",
+        owner_gitea_login="x", webhook_secret="x",
+    )
+    db.run_migrations(cfg)
+    if db._CONN is not None:
+        db._CONN.close()
+        db._CONN = None
+    db.init(cfg)
+    return cfg
+
+
+class _CorpusGitea:
+    """A content repo modelled as a flat {path: text} map, listing files under a
+    directory prefix and reading them back."""
+
+    def __init__(self, tree: dict[str, str]):
+        self._tree = tree
+
+    async def list_dir(self, org, repo, path, ref="main"):
+        out = []
+        prefix = (path.rstrip("/") + "/") if path else ""
+        for p in self._tree:
+            if p.startswith(prefix) and "/" not in p[len(prefix):]:
+                out.append({"type": "file", "name": p.split("/")[-1], "path": p})
+        return out
+
+    async def read_file(self, org, repo, path, ref="main"):
+        t = self._tree.get(path)
+        return (t, "sha-" + path) if t is not None else None
+
+
+def _entry_md(slug, title):
+    return f"---\nslug: {slug}\ntitle: {title}\nstate: active\n---\nbody\n"
+
+
+def _seed_project_with_two_collections():
+    db.conn().execute(
+        "INSERT OR REPLACE INTO projects (id, name, content_repo, visibility, updated_at) "
+        "VALUES ('ohm','Ohm','ohm-rfc','public', datetime('now'))")
+    for cid, sub in [("default", ""), ("features", "features")]:
+        db.conn().execute(
+            "INSERT OR REPLACE INTO collections (id, project_id, type, subfolder, initial_state, "
+            "visibility, created_at, updated_at) VALUES (?, 'ohm','document',?, "
+            "'super-draft','public', datetime('now'), datetime('now'))", (cid, sub))
+
+
+def test_mirror_keys_entries_by_collection():
+    cfg = _db()
+    _seed_project_with_two_collections()
+    gitea = _CorpusGitea({
+        "rfcs/a.md": _entry_md("a", "Default A"),
+        "features/rfcs/b.md": _entry_md("b", "Feature B"),
+    })
+    asyncio.run(cache.refresh_meta_repo(cfg, gitea))
+    got = {(r["collection_id"], r["slug"]) for r in
+           db.conn().execute("SELECT collection_id, slug FROM cached_rfcs")}
+    assert got == {("default", "a"), ("features", "b")}
+
+
+# --- collection-scoped serve + propose (full app) -----------------------------
+
+from fastapi.testclient import TestClient  # noqa: E402
+from test_propose_vertical import (  # noqa: E402,F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _add_features_collection(content_repo="meta"):
+    """Add a named 'features' collection (subfolder 'features') under the seeded
+    default project, plus a single entry under features/rfcs/ in the db cache."""
+    db.conn().execute(
+        "INSERT OR REPLACE INTO collections (id, project_id, type, subfolder, "
+        "initial_state, visibility, name, created_at, updated_at) VALUES "
+        "('features','default','document','features','super-draft','public','Features', "
+        "datetime('now'), datetime('now'))")
+
+
+def test_scoped_list_returns_only_that_collection(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_features_collection()
+        # Seed one entry under each collection's rfcs dir + mirror them in.
+        fake.files[("wiggleverse", "meta", "main", "rfcs/a.md")] = {
+            "content": _entry_md("a", "Default A"), "sha": "sa"}
+        fake.files[("wiggleverse", "meta", "main", "features/rfcs/b.md")] = {
+            "content": _entry_md("b", "Feature B"), "sha": "sb"}
+        from app import cache as cache_mod, gitea as gitea_mod
+        from app.config import load_config
+        cfg = load_config()
+        asyncio.run(cache_mod.refresh_meta_repo(cfg, gitea_mod.Gitea(cfg)))
+
+        r = client.get("/api/projects/default/collections/features/rfcs")
+        assert r.status_code == 200, r.text
+        assert [i["slug"] for i in r.json()["items"]] == ["b"]
+        # The default collection still serves only its own entry.
+        r2 = client.get("/api/projects/default/collections/default/rfcs")
+        assert [i["slug"] for i in r2.json()["items"]] == ["a"]
+
+
+def test_scoped_propose_writes_into_collection_subfolder(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_features_collection()
+        provision_user_row(user_id=3, login="alice", role="contributor")
+        # §22 S3: an explicitly-created collection requires an explicit scope
+        # grant to write (the grandfathered baseline covers only `default`).
+        db.conn().execute(
+            "INSERT OR REPLACE INTO memberships (scope_type, scope_id, user_id, role) "
+            "VALUES ('collection', 'features', 3, 'contributor')")
+        sign_in_as(client, user_id=3, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        r = client.post(
+            "/api/projects/default/collections/features/rfcs/propose",
+            json={"title": "New B", "slug": "newb", "pitch": "x", "tags": []})
+        assert r.status_code == 200, r.text
+        # The bot wrote the entry under features/rfcs/, not rfcs/.
+        keys = {(k[1], k[3]) for k in fake.files
+                if k[1] == "meta" and k[3].endswith("newb.md")}
+        assert ("meta", "features/rfcs/newb.md") in keys
+
+
+def test_scoped_routes_404_for_collection_outside_project(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.get("/api/projects/default/collections/nope/rfcs")
+        assert r.status_code == 404
+
+
+def test_s2_anonymous_empty_public_collection(app_with_fake_gitea):
+    """C3.6 (@S2): a public collection with no entries; an anonymous visitor
+    lands on its catalog → an empty catalog (200, no items), and the propose
+    action is not available to them (the propose route rejects anonymous)."""
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_features_collection()  # public, no entries
+        # Anonymous (no session cookie) reads the empty catalog — 200, [].
+        r = client.get("/api/projects/default/collections/features/rfcs")
+        assert r.status_code == 200, r.text
+        assert r.json()["items"] == []
+        # No propose action for an anonymous visitor.
+        r2 = client.post(
+            "/api/projects/default/collections/features/rfcs/propose",
+            json={"title": "X", "slug": "x", "pitch": "p", "tags": []})
+        assert r2.status_code == 401

backend/tests/test_contributions_vertical.py

@@ -0,0 +1,236 @@
+"""v0.29.0 / roadmap #28 Parts 2 & 3 — create-RFC offers + contribute-to-
+pending requests.
+
+Two layers, mirroring test_rfc_links_vertical.py:
+
+  * The PR-view scanner surfaces `rfc-pending` (Part 3) and `rfc-candidate`
+    (Part 2) segments alongside Part 1's `rfc` links.
+  * The contribute-request flow end-to-end: a non-owner asks, each owner
+    gets an actionable §15 notification, accept fires #12's invite flow,
+    decline notifies the requester.
+
+Reuses the FakeGitea + seed/session helpers from the existing suites.
+"""
+from __future__ import annotations
+
+import json
+
+from fastapi.testclient import TestClient
+
+from app import db
+
+from test_propose_vertical import (  # noqa: F401
+    FakeGitea,
+    app_with_fake_gitea,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+from test_rfc_view_vertical import SEED_BODY, seed_active_rfc
+from test_super_draft_vertical import seed_super_draft
+from test_rfc_links_vertical import _open_pr_on
+
+
+def _set_owner(slug: str, login: str) -> None:
+    db.conn().execute(
+        "UPDATE cached_rfcs SET owners_json = ? WHERE slug = ?",
+        (json.dumps([login]), slug),
+    )
+
+
+def _set_tags(slug: str, tags: list[str]) -> None:
+    db.conn().execute(
+        "UPDATE cached_rfcs SET tags_json = ? WHERE slug = ?",
+        (json.dumps(tags), slug),
+    )
+
+
+def _segs(segments, kind):
+    return [s for s in segments if s["type"] == kind]
+
+
+# ---------------------------------------------------------------------------
+# Part 2 + Part 3 — scanner surfaces on the PR view
+# ---------------------------------------------------------------------------
+
+
+def test_pending_and_candidate_segments_on_pr(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        # Host active RFC (OHM — single word, contributes no keys itself)
+        # carrying a multi-word tag with no defining RFC: the Part 2
+        # candidate. And a pending super-draft owned by alice: the Part 3
+        # contribute target.
+        seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
+        _set_tags("ohm", ["memory model", "identity"])
+        seed_super_draft(fake, slug="open-human-model", title="Open Human Model",
+                         pitch="A framework for representing humans.", proposed_by="alice")
+        _set_owner("open-human-model", "alice")
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor")
+
+        pr_number = _open_pr_on(
+            client, fake, host_slug="ohm",
+            description="This builds on the Open Human Model and the memory model.",
+        )
+        pr = client.get(f"/api/rfcs/ohm/prs/{pr_number}").json()
+        segs = pr["description_segments"]
+
+        pending = _segs(segs, "rfc-pending")
+        assert len(pending) == 1
+        assert pending[0]["slug"] == "open-human-model"
+        assert pending[0]["label"] == "Open Human Model"
+        assert pending[0]["owner"] == "Alice"   # display_name of the owner
+
+        candidate = _segs(segs, "rfc-candidate")
+        assert len(candidate) == 1
+        assert candidate[0]["term"] == "memory model"
+        # "identity" is a single-word tag — deliberately NOT a candidate.
+        assert all("identity" not in s.get("term", "") for s in candidate)
+
+
+# ---------------------------------------------------------------------------
+# Part 3 — the contribute-request flow
+# ---------------------------------------------------------------------------
+
+
+def _seed_pending_owned_by_alice(fake):
+    provision_user_row(user_id=2, login="alice", role="contributor")
+    provision_user_row(user_id=3, login="bob", role="contributor")
+    seed_super_draft(fake, slug="open-human-model", title="Open Human Model",
+                     pitch="A framework.", proposed_by="alice")
+    _set_owner("open-human-model", "alice")
+
+
+_REQUEST = {
+    "matched_term": "Open Human Model",
+    "who_i_am": "Bob, a researcher",
+    "why": "I have relevant prior work to bring.",
+    "use_case": "Building an identity tool.",
+}
+
+
+def test_request_accept_invites_and_notifies(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_pending_owned_by_alice(fake)
+
+        # Bob asks to contribute.
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        r = client.post("/api/rfcs/open-human-model/contribution-requests", json=_REQUEST)
+        assert r.status_code == 200, r.text
+        request_id = r.json()["id"]
+        assert r.json()["status"] == "pending"
+
+        # A second ask while pending is a 409, not a duplicate row.
+        assert client.post("/api/rfcs/open-human-model/contribution-requests",
+                           json=_REQUEST).status_code == 409
+
+        # Alice (owner) sees the actionable notification with full detail.
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        inbox = client.get("/api/notifications").json()
+        reqs = [i for i in inbox["items"]
+                if i["event_kind"] == "contribution_request_on_pending_rfc"]
+        assert len(reqs) == 1
+        assert "wants to contribute" in reqs[0]["summary"]
+        assert reqs[0]["extras"]["who_i_am"] == "Bob, a researcher"
+        assert reqs[0]["extras"]["request_id"] == request_id
+
+        # Alice accepts → #12 invitation minted for bob's email.
+        acc = client.post(f"/api/rfcs/open-human-model/contribution-requests/{request_id}/accept")
+        assert acc.status_code == 200, acc.text
+        assert acc.json()["status"] == "accepted"
+        assert acc.json()["invitation_id"]
+
+        inv = db.conn().execute(
+            "SELECT invitee_email, role_in_rfc, status FROM rfc_invitations "
+            "WHERE rfc_slug = 'open-human-model'"
+        ).fetchone()
+        assert inv["invitee_email"] == "bob@test"
+        assert inv["role_in_rfc"] == "contributor"
+        assert inv["status"] == "pending"
+
+        # The request is settled — re-accepting is a 409.
+        assert client.post(
+            f"/api/rfcs/open-human-model/contribution-requests/{request_id}/accept"
+        ).status_code == 409
+
+        # Bob gets the accepted echo in his inbox.
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        bob_kinds = [i["event_kind"] for i in client.get("/api/notifications").json()["items"]]
+        assert "contribution_request_accepted" in bob_kinds
+
+
+def test_decline_notifies_requester(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_pending_owned_by_alice(fake)
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        request_id = client.post(
+            "/api/rfcs/open-human-model/contribution-requests", json=_REQUEST
+        ).json()["id"]
+
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        dec = client.post(f"/api/rfcs/open-human-model/contribution-requests/{request_id}/decline")
+        assert dec.status_code == 200, dec.text
+        assert dec.json()["status"] == "declined"
+
+        row = db.conn().execute(
+            "SELECT status FROM contribution_requests WHERE id = ?", (request_id,)
+        ).fetchone()
+        assert row["status"] == "declined"
+
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        bob_kinds = [i["event_kind"] for i in client.get("/api/notifications").json()["items"]]
+        assert "contribution_request_declined" in bob_kinds
+
+
+def test_owner_cannot_request_own_rfc(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_pending_owned_by_alice(fake)
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        r = client.post("/api/rfcs/open-human-model/contribution-requests", json=_REQUEST)
+        assert r.status_code == 409
+        assert "own" in r.json()["detail"].lower()
+
+
+def test_request_on_active_rfc_rejected(app_with_fake_gitea):
+    # The contribute offer only exists for pending super-drafts; an active
+    # RFC uses the Part-1 link instead.
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=3, login="bob", role="contributor")
+        seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        r = client.post("/api/rfcs/ohm/contribution-requests", json=_REQUEST)
+        assert r.status_code == 409
+
+
+def test_contribution_target_eligibility(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_pending_owned_by_alice(fake)
+
+        # Anonymous: not eligible, told to sign in.
+        t = client.get("/api/rfcs/open-human-model/contribution-target").json()
+        assert t["eligible"] is False
+        assert "sign in" in (t["reason"] or "").lower()
+        assert t["owner"] == "Alice"
+
+        # Bob: eligible until he has a pending ask, then not.
+        sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        assert client.get("/api/rfcs/open-human-model/contribution-target").json()["eligible"] is True
+        client.post("/api/rfcs/open-human-model/contribution-requests", json=_REQUEST)
+        after = client.get("/api/rfcs/open-human-model/contribution-target").json()
+        assert after["already_requested"] is True
+        assert after["eligible"] is False

backend/tests/test_device_trust_vertical.py

@@ -0,0 +1,494 @@
+"""End-to-end integration tests for the v0.11.0 trust-device vertical
+(§6.2, roadmap item #9).
+
+After a successful OTC or passcode sign-in with `trust_device=true`
+on the body, the server mints a fresh `device_trust` row and sets the
+`rfc_device_trust` cookie. On a subsequent visit, the cookie carries
+a session re-established by `POST /auth/device-trust/start`. The
+tests below prove:
+
+  * `trust_device=false` (default, including omitted) on OTC verify
+    does NOT set the device-trust cookie and does NOT insert a row.
+  * `trust_device=true` on OTC verify DOES set the cookie (HttpOnly +
+    Secure + SameSite=Lax + 30-day Max-Age) and DOES insert a row.
+    The row's hash is NOT the raw token; only the hash lives in the
+    database.
+  * Same shape for passcode verify.
+  * On a returning visit with the cookie, `POST /auth/device-trust/start`
+    re-establishes the session — `GET /api/auth/me` reads the right
+    user without an OTC roundtrip.
+  * `last_seen_at` refreshes on a successful lookup.
+  * `POST /auth/device-trust/start` with no cookie returns 401.
+  * `POST /auth/device-trust/start` with a forged / unknown cookie
+    returns 401 + clears the cookie.
+  * A revoked row refuses the cookie (401) and clears it.
+  * An expired row refuses the cookie (401) and clears it.
+  * `GET /api/auth/me/devices` lists the user's active rows.
+  * `DELETE /api/auth/me/devices/{id}` revokes a single row.
+  * `DELETE /api/auth/me/devices/{id}` for another user's row reads 404.
+  * `DELETE /api/auth/me/devices` revokes every active row.
+  * Constant-time path: bcrypt.checkpw guards lookup; the raw token
+    is never written to logs or to the DB.
+
+The fakes from `test_propose_vertical` give us a working app harness.
+The OTC envelope buffer from `test_otc_vertical` is reused for the
+OTC roundtrips this suite needs.
+"""
+from __future__ import annotations
+
+import pytest
+
+from test_propose_vertical import (  # noqa: F401
+    FakeGitea,
+    app_with_fake_gitea,
+    provision_user_row,
+    tmp_env,
+)
+
+
+# ---------------------------------------------------------------------------
+# Helpers — mirror the OTC suite's outbound-buffer helpers.
+# ---------------------------------------------------------------------------
+
+
+COOKIE_NAME = "rfc_device_trust"
+
+# The device-trust cookie is set with Secure=True, which httpx (the
+# TestClient's underlying transport) will only return on an https
+# scheme. We use a `base_url="https://testserver"` so the cookie
+# roundtrips faithfully — that mirrors how production deployments
+# serve the framework (per the v0.11.0 upgrade-step requiring HTTPS).
+HTTPS_BASE = "https://testserver"
+
+
+def _reset_outbound():
+    from app import email as email_mod
+    email_mod.reset_sent_envelopes()
+
+
+def _outbound_otc_codes(to_address: str | None = None) -> list[str]:
+    from app import email as email_mod
+    out = []
+    for env in email_mod.sent_envelopes():
+        if env.get("kind") != "otc":
+            continue
+        if to_address is not None and env["to"] != to_address:
+            continue
+        for line in env["body"].splitlines():
+            tok = line.strip()
+            if tok.isdigit() and len(tok) == 6:
+                out.append(tok)
+                break
+    return out
+
+
+def _sign_in_via_otc(client, email: str, *, trust_device: bool = False) -> None:
+    r = client.post("/auth/otc/request", json={"email": email})
+    assert r.status_code == 200, r.text
+    code = _outbound_otc_codes(email)[-1]
+    body = {"email": email, "code": code, "trust_device": trust_device}
+    r = client.post("/auth/otc/verify", json=body)
+    assert r.status_code == 200, r.text
+
+
+def _device_rows_for_email(email: str) -> list[dict]:
+    from app import db
+    rows = db.conn().execute(
+        """
+        SELECT dt.*
+          FROM device_trust dt
+          JOIN users u ON u.id = dt.user_id
+         WHERE u.email = ? COLLATE NOCASE
+         ORDER BY dt.id
+        """,
+        (email,),
+    ).fetchall()
+    return [dict(r) for r in rows]
+
+
+# ---------------------------------------------------------------------------
+# trust_device flag controls cookie issuance
+# ---------------------------------------------------------------------------
+
+
+def test_otc_verify_without_trust_device_does_not_issue_cookie(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        _sign_in_via_otc(client, "alice@example.com", trust_device=False)
+        # No cookie set on the response.
+        assert COOKIE_NAME not in {c.name for c in client.cookies.jar}
+        # No row inserted.
+        assert _device_rows_for_email("alice@example.com") == []
+
+
+def test_otc_verify_with_trust_device_issues_cookie_and_row(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+            headers={"User-Agent": "Mozilla/5.0 (TestBrowser)"},
+        )
+        assert r.status_code == 200, r.text
+
+        # Cookie present on the response.
+        set_cookie = r.headers.get("set-cookie", "")
+        assert COOKIE_NAME in set_cookie
+        # Cookie attribute set asserts the spec'd shape. Starlette emits
+        # the attribute names case-insensitively (`samesite=lax`,
+        # `httponly`); we normalize when asserting.
+        lower = set_cookie.lower()
+        assert "httponly" in lower
+        assert "secure" in lower
+        assert "samesite=lax" in lower
+        assert "max-age=" in lower
+
+        # Row inserted; hash is not the raw token.
+        rows = _device_rows_for_email("alice@example.com")
+        assert len(rows) == 1
+        row = rows[0]
+        assert row["revoked_at"] is None
+        assert row["user_agent"] == "Mozilla/5.0 (TestBrowser)"
+        cookie_token = client.cookies.get(COOKIE_NAME)
+        assert cookie_token
+        assert cookie_token != row["device_token_hash"]
+        # bcrypt hash shape (starts with $2)
+        assert row["device_token_hash"].startswith("$2")
+
+
+def test_passcode_verify_with_trust_device_issues_cookie(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        _sign_in_via_otc(client, "alice@example.com")
+
+        # Set a passcode.
+        r = client.post("/auth/passcode/set", json={"passcode": "secret123"})
+        assert r.status_code == 200, r.text
+
+        # Sign out so the passcode verify path is the active sign-in.
+        client.cookies.clear()
+
+        # Passcode verify with trust_device=true issues a row.
+        r = client.post(
+            "/auth/passcode/verify",
+            json={"email": "alice@example.com", "passcode": "secret123", "trust_device": True},
+            headers={"User-Agent": "Test/Phone"},
+        )
+        assert r.status_code == 200, r.text
+        set_cookie = r.headers.get("set-cookie", "")
+        assert COOKIE_NAME in set_cookie
+
+        rows = _device_rows_for_email("alice@example.com")
+        assert len(rows) == 1
+        assert rows[0]["user_agent"] == "Test/Phone"
+
+
+# ---------------------------------------------------------------------------
+# /auth/device-trust/start
+# ---------------------------------------------------------------------------
+
+
+def test_device_trust_start_with_no_cookie_returns_401(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 401
+
+
+def test_device_trust_start_with_valid_cookie_establishes_session(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        # Trust the device.
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+        )
+        assert r.status_code == 200, r.text
+        trust_cookie = client.cookies.get(COOKIE_NAME)
+        assert trust_cookie
+
+        # Clear the session cookie so only the device-trust cookie is in
+        # play. We keep `rfc_device_trust` and drop `rfc_session`.
+        for cookie in list(client.cookies.jar):
+            if cookie.name != COOKIE_NAME:
+                client.cookies.jar.clear(cookie.domain, cookie.path, cookie.name)
+
+        # The session cookie is gone — /api/auth/me reads anonymous.
+        me = client.get("/api/auth/me").json()
+        assert me["authenticated"] is False
+
+        # Hit the trust-start endpoint; the cookie re-establishes the session.
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 200, r.text
+        assert r.json()["user"]["email"] == "alice@example.com"
+
+        # /api/auth/me now reads authenticated.
+        me = client.get("/api/auth/me").json()
+        assert me["authenticated"] is True
+        assert me["user"]["email"] == "alice@example.com"
+
+
+def test_device_trust_start_refreshes_last_seen_at(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+        )
+        assert r.status_code == 200, r.text
+
+        # Force the existing row's last_seen_at into the past so we can
+        # assert the refresh moved it forward.
+        db.conn().execute(
+            """
+            UPDATE device_trust
+               SET last_seen_at = datetime('now', '-7 days')
+            """
+        )
+
+        # Hit the start endpoint.
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 200, r.text
+
+        # last_seen_at is now recent (within the last minute).
+        row = db.conn().execute(
+            "SELECT last_seen_at, datetime('now') >= datetime(last_seen_at, '-1 minute') AS fresh FROM device_trust LIMIT 1"
+        ).fetchone()
+        assert row["fresh"] == 1
+
+
+def test_device_trust_start_with_revoked_row_refuses_and_clears(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+        )
+        assert r.status_code == 200, r.text
+
+        # Revoke the row out-of-band.
+        db.conn().execute(
+            "UPDATE device_trust SET revoked_at = datetime('now')"
+        )
+
+        # Now the start endpoint refuses + clears the cookie.
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 401
+        # The cookie is cleared via a Set-Cookie header with Max-Age=0
+        # (Starlette's `delete_cookie` shape).
+        set_cookie = r.headers.get("set-cookie", "")
+        assert COOKIE_NAME in set_cookie
+        assert "Max-Age=0" in set_cookie or 'expires=Thu, 01 Jan 1970' in set_cookie.lower().replace("expires=thu", "expires=Thu")
+
+
+def test_device_trust_start_with_expired_row_refuses_and_clears(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+        )
+        assert r.status_code == 200, r.text
+
+        # Backdate the expiry into the past.
+        db.conn().execute(
+            "UPDATE device_trust SET expires_at = datetime('now', '-1 day')"
+        )
+
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 401
+        set_cookie = r.headers.get("set-cookie", "")
+        assert COOKIE_NAME in set_cookie
+
+
+def test_device_trust_start_with_forged_cookie_refuses_and_clears(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        # No real row; just paste a cookie value.
+        client.cookies.set(COOKIE_NAME, "definitely-not-a-real-token-value-xxx")
+        r = client.post("/auth/device-trust/start")
+        assert r.status_code == 401
+        set_cookie = r.headers.get("set-cookie", "")
+        assert COOKIE_NAME in set_cookie
+
+
+# ---------------------------------------------------------------------------
+# /api/auth/me/devices — list + revoke
+# ---------------------------------------------------------------------------
+
+
+def test_list_devices_requires_session(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        r = client.get("/api/auth/me/devices")
+        assert r.status_code == 401
+
+
+def test_list_devices_returns_active_rows_only(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        _sign_in_via_otc(client, "alice@example.com", trust_device=True)
+
+        # Add a second trusted device by re-running the verify flow.
+        # OTC has a per-email cooldown, so drop the cooldown rather
+        # than waiting it out.
+        db.conn().execute("UPDATE otc_codes SET consumed_at = datetime('now', '-1 hour'), created_at = datetime('now', '-1 hour')")
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+            headers={"User-Agent": "Test/Tablet"},
+        )
+        assert r.status_code == 200, r.text
+
+        # Revoke one row directly.
+        db.conn().execute(
+            "UPDATE device_trust SET revoked_at = datetime('now') WHERE id = 1"
+        )
+
+        # /api/auth/me/devices returns only the un-revoked one.
+        r = client.get("/api/auth/me/devices")
+        assert r.status_code == 200, r.text
+        items = r.json()["items"]
+        assert len(items) == 1
+        assert items[0]["user_agent"] == "Test/Tablet"
+
+
+def test_revoke_single_device_kills_the_row(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        _sign_in_via_otc(client, "alice@example.com", trust_device=True)
+
+        r = client.get("/api/auth/me/devices")
+        assert r.status_code == 200, r.text
+        items = r.json()["items"]
+        assert len(items) == 1
+        device_id = items[0]["id"]
+
+        # Revoke it.
+        r = client.delete(f"/api/auth/me/devices/{device_id}")
+        assert r.status_code == 200, r.text
+
+        # List is empty.
+        r = client.get("/api/auth/me/devices")
+        assert r.json()["items"] == []
+
+        # The row in the table has revoked_at populated.
+        row = db.conn().execute(
+            "SELECT revoked_at FROM device_trust WHERE id = ?", (device_id,)
+        ).fetchone()
+        assert row["revoked_at"] is not None
+
+
+def test_revoke_other_users_device_reads_404(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        # Alice trusts a device.
+        _sign_in_via_otc(client, "alice@example.com", trust_device=True)
+        alice_device_id = client.get("/api/auth/me/devices").json()["items"][0]["id"]
+
+        # Bob signs in (without a trusted device of his own).
+        client.cookies.clear()
+        db.conn().execute("UPDATE otc_codes SET consumed_at = datetime('now', '-1 hour'), created_at = datetime('now', '-1 hour')")
+        _sign_in_via_otc(client, "bob@example.com", trust_device=False)
+
+        # Bob tries to revoke Alice's row by id.
+        r = client.delete(f"/api/auth/me/devices/{alice_device_id}")
+        assert r.status_code == 404
+
+        # Alice's row is still active.
+        row = db.conn().execute(
+            "SELECT revoked_at FROM device_trust WHERE id = ?", (alice_device_id,)
+        ).fetchone()
+        assert row["revoked_at"] is None
+
+
+def test_revoke_all_devices_kills_every_active_row(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app, base_url=HTTPS_BASE) as client:
+        _reset_outbound()
+        _sign_in_via_otc(client, "alice@example.com", trust_device=True)
+
+        # Add a second device.
+        db.conn().execute("UPDATE otc_codes SET consumed_at = datetime('now', '-1 hour'), created_at = datetime('now', '-1 hour')")
+        r = client.post("/auth/otc/request", json={"email": "alice@example.com"})
+        assert r.status_code == 200, r.text
+        code = _outbound_otc_codes("alice@example.com")[-1]
+        r = client.post(
+            "/auth/otc/verify",
+            json={"email": "alice@example.com", "code": code, "trust_device": True},
+        )
+        assert r.status_code == 200, r.text
+
+        # Two active rows.
+        assert len(client.get("/api/auth/me/devices").json()["items"]) == 2
+
+        # Revoke all.
+        r = client.delete("/api/auth/me/devices")
+        assert r.status_code == 200, r.text
+        assert r.json()["revoked"] == 2
+
+        # List is empty.
+        assert client.get("/api/auth/me/devices").json()["items"] == []

backend/tests/test_docs_sessions_vertical.py

@@ -0,0 +1,384 @@
+"""v0.19.0 / roadmap item #30 — `/api/docs/sessions/*` endpoints.
+
+The framework mediates reads against the public
+`wiggleverse/ohm-session-history` gitea repo so the rendered
+`/docs/sessions/*` surface inherits the same chrome as `/docs/user-guide`.
+This test suite covers the four endpoints + the in-process TTL cache,
+mocking the upstream HTTP via `httpx.MockTransport` (the same shape the
+rest of the test suite uses for Gitea).
+
+The tests do NOT spin up the full FakeGitea — they only need to mock
+the gitea raw URL surface (and the contents API for the session-index
+endpoint). Each test owns its mock transport so we can dial in 200 /
+404 / 5xx / timeout responses per case.
+
+Path-validation tests intentionally bypass the network — a malformed
+`nnnn` or `filename` MUST be rejected at the route layer before any
+upstream call is made.
+"""
+from __future__ import annotations
+
+import json
+
+import httpx
+import pytest
+from fastapi.testclient import TestClient
+
+from app import docs_sessions
+
+# Reuse the proven app-construction fixtures from the proposal vertical
+# (same shape every test file in this repo uses).
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea,
+    tmp_env,
+)
+
+
+# ---------------------------------------------------------------------------
+# Test scaffolding
+# ---------------------------------------------------------------------------
+
+
+class _UpstreamHandler:
+    """Records every URL the docs_sessions module fetched and returns
+    canned responses keyed by URL substring. Allows the test to assert
+    on call count (for cache verification) without needing a full Gitea
+    simulator.
+
+    `calls` tracks only URLs that hit the session-history host (the
+    `OHM_SESSION_HISTORY_*` bases) so reconciler/Gitea-side calls — which
+    also pass through this handler because `httpx.AsyncClient` is a
+    shared attribute the gitea-side fixture also monkeypatches — don't
+    inflate the count we use for cache-hit assertions.
+    """
+
+    _SESSION_HOST_MARKERS = ("ohm-session-history", "wiggleverse/ohm-session-history")
+
+    def __init__(self, responses: dict[str, tuple[int, str]]):
+        self.responses = responses
+        self.calls: list[str] = []
+
+    def __call__(self, request: httpx.Request) -> httpx.Response:
+        url = str(request.url)
+        if any(m in url for m in self._SESSION_HOST_MARKERS):
+            self.calls.append(url)
+        for key, (status, body) in self.responses.items():
+            if key in url:
+                return httpx.Response(status, text=body)
+        # Default: 404. Lets tests skip declaring "the rest is 404".
+        return httpx.Response(404, text="not found")
+
+
+@pytest.fixture
+def patched_httpx(monkeypatch, app_with_fake_gitea):  # noqa: F811
+    """Provide a hook the test can call to install a MockTransport.
+
+    Returns a closure: `install(handler)` patches `httpx.AsyncClient`
+    (via `app.docs_sessions.httpx.AsyncClient`) so every constructed
+    client uses the handler's transport.
+
+    M3 note: lifespan now calls `refresh_registry` which hits FakeGitea
+    via the gitea transport. Since `httpx` is a module singleton, installing
+    the docs transport would clobber the FakeGitea mock already installed
+    by `app_with_fake_gitea`. We use a COMPOSITE handler: Gitea API
+    requests (to `http://gitea.test/`) are delegated to FakeGitea; all
+    other requests go to the test-specific handler.
+    """
+    from httpx._client import AsyncClient as RealAsyncClient
+
+    _fake = app_with_fake_gitea[1]
+
+    def install(handler):
+        def composite(request: httpx.Request) -> httpx.Response:
+            if "gitea.test" in str(request.url):
+                return _fake.handle(request)
+            return handler(request)
+
+        def patched(*args, **kwargs):
+            kwargs["transport"] = httpx.MockTransport(composite)
+            return RealAsyncClient(*args, **kwargs)
+
+        monkeypatch.setattr("app.docs_sessions.httpx.AsyncClient", patched)
+        return handler
+
+    yield install
+
+
+@pytest.fixture
+def app(app_with_fake_gitea):
+    """Wrap the shared app fixture, resetting the docs-sessions cache so
+    cross-test state can't leak. Returns just the FastAPI app — the
+    fake-Gitea handle is irrelevant for the docs-sessions surface.
+    """
+    docs_sessions.reset_cache()
+    fastapi_app, _fake = app_with_fake_gitea
+    return fastapi_app
+
+
+# ---------------------------------------------------------------------------
+# Manifest endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_manifest_happy_path(app, patched_httpx):
+    manifest_body = json.dumps(
+        {
+            "0001": {"title": "Bootstrap"},
+            "0014": {"title": "Wave 7 driver"},
+        }
+    )
+    patched_httpx(
+        _UpstreamHandler({"sessions.json": (200, manifest_body)})
+    )
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/manifest")
+        assert r.status_code == 200, r.text
+        payload = r.json()
+        assert payload == {
+            "0001": {"title": "Bootstrap"},
+            "0014": {"title": "Wave 7 driver"},
+        }
+
+
+def test_manifest_empty_state(app, patched_httpx):
+    """A 404 from gitea means the manifest hasn't been published yet.
+    The endpoint returns HTTP 200 + `{}` so the frontend can render the
+    no-sessions-yet state without an error banner.
+    """
+    patched_httpx(_UpstreamHandler({"sessions.json": (404, "not found")}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/manifest")
+        assert r.status_code == 200, r.text
+        assert r.json() == {}
+
+
+def test_manifest_upstream_5xx_returns_502(app, patched_httpx):
+    patched_httpx(_UpstreamHandler({"sessions.json": (500, "internal")}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/manifest")
+        assert r.status_code == 502, r.text
+        body = r.json()
+        assert body["detail"]["error"] == "session-history fetch failed"
+
+
+# ---------------------------------------------------------------------------
+# About endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_about_happy_path(app, patched_httpx):
+    readme = "# OHM session history\n\nWelcome.\n"
+    patched_httpx(_UpstreamHandler({"README.md": (200, readme)}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/about")
+        assert r.status_code == 200, r.text
+        assert "text/markdown" in r.headers["content-type"]
+        assert r.text == readme
+
+
+def test_about_404(app, patched_httpx):
+    patched_httpx(_UpstreamHandler({"README.md": (404, "")}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/about")
+        assert r.status_code == 404, r.text
+
+
+def test_about_upstream_5xx_returns_502(app, patched_httpx):
+    patched_httpx(_UpstreamHandler({"README.md": (503, "down")}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/about")
+        assert r.status_code == 502, r.text
+
+
+# ---------------------------------------------------------------------------
+# Transcript endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_transcript_happy_path(app, patched_httpx):
+    body = "# Session 0017.1 — Transcript\n\nbody.\n"
+    fname = "SESSION-0017.1-TRANSCRIPT-2026-05-28T08-50--2026-05-28T11-20.md"
+    patched_httpx(_UpstreamHandler({fname: (200, body)}))
+    with TestClient(app) as client:
+        r = client.get(f"/api/docs/sessions/0017/{fname}")
+        assert r.status_code == 200, r.text
+        assert "text/markdown" in r.headers["content-type"]
+        assert r.text == body
+
+
+def test_transcript_404(app, patched_httpx):
+    fname = "SESSION-9999.0-TRANSCRIPT-2026-01-01T00-00--2026-01-01T00-01.md"
+    patched_httpx(_UpstreamHandler({}))  # everything 404s
+    with TestClient(app) as client:
+        r = client.get(f"/api/docs/sessions/9999/{fname}")
+        assert r.status_code == 404, r.text
+
+
+def test_transcript_rejects_invalid_session_dir(app, patched_httpx):
+    """`nnnn` must be exactly 4 digits. `abcd` fails before any
+    network call.
+    """
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r = client.get(
+            "/api/docs/sessions/abcd/"
+            "SESSION-0001.0-TRANSCRIPT-2026-01-01T00-00--2026-01-01T00-01.md"
+        )
+        assert r.status_code == 400, r.text
+    assert handler.calls == [], "rejected path must not hit the network"
+
+
+def test_transcript_rejects_path_traversal(app, patched_httpx):
+    """A filename that doesn't match the SESSION-NNNN.M-TRANSCRIPT regex
+    is rejected. `../etc/passwd` doesn't match; neither does the legacy
+    flat-root `SESSION-A-TRANSCRIPT.md`.
+    """
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        # Path traversal — but FastAPI normalizes `..` in the path before
+        # routing, so this resolves to /api/docs/sessions/0001/etc/passwd
+        # which routes to the same handler with filename=etc/passwd, and
+        # gets rejected as an invalid transcript filename. Even if the
+        # normalization didn't apply (some intermediary), the regex
+        # check rejects anything not matching the SESSION- prefix.
+        r = client.get(
+            "/api/docs/sessions/0001/etc%2Fpasswd"
+        )
+        # 400 (filename validation) or 404 (path didn't match the
+        # route); both reject before any network call. Either is
+        # acceptable — what matters is that we never fetched it.
+        assert r.status_code in (400, 404), r.text
+    assert handler.calls == [], "rejected path must not hit the network"
+
+
+def test_transcript_rejects_legacy_flat_filename(app, patched_httpx):
+    """Legacy `SESSION-A-TRANSCRIPT.md` (letter form) doesn't match the
+    numeric regex — by design, since post-#23 transcripts live in
+    `NNNN/` folders with numeric names. Reject 400.
+    """
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/0001/SESSION-A-TRANSCRIPT.md")
+        assert r.status_code == 400, r.text
+    assert handler.calls == [], "rejected path must not hit the network"
+
+
+def test_transcript_upstream_5xx_returns_502(app, patched_httpx):
+    fname = "SESSION-0001.0-TRANSCRIPT-2026-01-01T00-00--2026-01-01T00-01.md"
+    patched_httpx(_UpstreamHandler({fname: (502, "bad gateway")}))
+    with TestClient(app) as client:
+        r = client.get(f"/api/docs/sessions/0001/{fname}")
+        assert r.status_code == 502, r.text
+
+
+# ---------------------------------------------------------------------------
+# Session-index endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_session_index_happy_path(app, patched_httpx):
+    """The contents API returns a JSON list of file entries. The
+    endpoint filters to entries that match the transcript regex and
+    sorts them.
+    """
+    # Two transcripts (driver + subagent) + a non-transcript sibling
+    # that must be filtered out.
+    listing = json.dumps(
+        [
+            {
+                "name": "SESSION-0017.0-TRANSCRIPT-"
+                "2026-05-28T08-30--2026-05-28T12-00.md",
+                "type": "file",
+            },
+            {
+                "name": "SESSION-0017.1-TRANSCRIPT-"
+                "2026-05-28T08-50--2026-05-28T11-20.md",
+                "type": "file",
+            },
+            {"name": "notes.md", "type": "file"},  # not a transcript
+            {"name": "attached-dir", "type": "dir"},  # not a file
+        ]
+    )
+    patched_httpx(_UpstreamHandler({"/contents/0017": (200, listing)}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/0017/index")
+        assert r.status_code == 200, r.text
+        files = r.json()["files"]
+        assert files == [
+            "SESSION-0017.0-TRANSCRIPT-2026-05-28T08-30--2026-05-28T12-00.md",
+            "SESSION-0017.1-TRANSCRIPT-2026-05-28T08-50--2026-05-28T11-20.md",
+        ]
+
+
+def test_session_index_404(app, patched_httpx):
+    patched_httpx(_UpstreamHandler({}))  # everything 404s
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/9999/index")
+        assert r.status_code == 404, r.text
+
+
+def test_session_index_rejects_invalid_session_dir(app, patched_httpx):
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r = client.get("/api/docs/sessions/abc/index")
+        assert r.status_code == 400, r.text
+    assert handler.calls == [], "rejected path must not hit the network"
+
+
+# ---------------------------------------------------------------------------
+# Cache behavior
+# ---------------------------------------------------------------------------
+
+
+def test_manifest_cache_hits_within_ttl(app, patched_httpx, monkeypatch):
+    """Two consecutive manifest calls within the TTL window should
+    issue exactly one HTTP request to gitea.
+    """
+    # Generous TTL so the test never races.
+    monkeypatch.setenv("OHM_DOCS_SESSIONS_MANIFEST_TTL_SEC", "60")
+    handler = _UpstreamHandler(
+        {"sessions.json": (200, json.dumps({"0001": {"title": "x"}}))}
+    )
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r1 = client.get("/api/docs/sessions/manifest")
+        r2 = client.get("/api/docs/sessions/manifest")
+    assert r1.status_code == 200
+    assert r2.status_code == 200
+    assert len(handler.calls) == 1, (
+        f"expected one upstream call, got {handler.calls}"
+    )
+
+
+def test_transcript_cache_hits_within_ttl(app, patched_httpx, monkeypatch):
+    monkeypatch.setenv("OHM_DOCS_SESSIONS_CONTENT_TTL_SEC", "300")
+    fname = "SESSION-0001.0-TRANSCRIPT-2026-01-01T00-00--2026-01-01T00-01.md"
+    handler = _UpstreamHandler({fname: (200, "# body\n")})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r1 = client.get(f"/api/docs/sessions/0001/{fname}")
+        r2 = client.get(f"/api/docs/sessions/0001/{fname}")
+    assert r1.status_code == 200
+    assert r2.status_code == 200
+    assert len(handler.calls) == 1
+
+
+def test_transcript_404_is_cached(app, patched_httpx, monkeypatch):
+    """Negative caching: a 404 result is cached at the content TTL so a
+    deployment with no published transcripts doesn't hammer gitea on
+    every navigation. Documented in `docs_sessions.fetch_transcript`.
+    """
+    monkeypatch.setenv("OHM_DOCS_SESSIONS_CONTENT_TTL_SEC", "300")
+    fname = "SESSION-9999.0-TRANSCRIPT-2026-01-01T00-00--2026-01-01T00-01.md"
+    handler = _UpstreamHandler({})  # everything 404s
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r1 = client.get(f"/api/docs/sessions/9999/{fname}")
+        r2 = client.get(f"/api/docs/sessions/9999/{fname}")
+    assert r1.status_code == 404
+    assert r2.status_code == 404
+    assert len(handler.calls) == 1, "negative caching should suppress the 2nd call"

backend/tests/test_docs_specs_vertical.py

@@ -0,0 +1,478 @@
+"""v0.20.0 — `/api/docs/specs/*` endpoints.
+
+Sibling of `test_docs_sessions_vertical.py`. The framework mediates
+reads of the configured framework-spec URLs (default: rfc-app's own
+SPEC.md + flotilla's SPEC.md on `git.wiggleverse.org`) so the
+`/docs/specs/*` surface inherits the same chrome as
+`/docs/user-guide` and `/docs/sessions/*`.
+
+This file covers:
+
+  - The manifest endpoint with the framework default
+  - The manifest endpoint with an overridden `OHM_DOCS_SPECS` JSON value
+  - Slug validation at the route layer (rejects `..`, `/`, `~`,
+    uppercase, whitespace, path traversal attempts)
+  - Gitea 200 / 404 / 5xx response mapping
+  - Negative caching (404 is cached, not re-fetched within TTL)
+  - Malformed `OHM_DOCS_SPECS` → fallback to the default + a logged
+    warning (asserted by caplog)
+  - A manifest entry that fails per-entry validation (bad slug,
+    missing field) is dropped, with the rest of the list retained
+
+Mocking approach: same as docs_sessions — `httpx.MockTransport`
+substituted into `app.docs_specs.httpx.AsyncClient` via a fixture.
+"""
+from __future__ import annotations
+
+import json
+import logging
+
+import httpx
+import pytest
+from fastapi.testclient import TestClient
+
+from app import docs_specs
+
+# Reuse the proven app-construction fixtures from the proposal vertical
+# (same shape every test file in this repo uses).
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea,
+    tmp_env,
+)
+
+
+# ---------------------------------------------------------------------------
+# Test scaffolding
+# ---------------------------------------------------------------------------
+
+
+class _UpstreamHandler:
+    """Records every URL the docs_specs module fetched and returns
+    canned responses keyed by URL substring. Lets the test assert on
+    call count (for cache verification) without booting a full upstream
+    simulator.
+
+    `calls` tracks only URLs that hit a host configured in the spec
+    manifest under test — so unrelated httpx clients (gitea-side
+    fixtures, etc.) don't inflate the count we use for cache-hit
+    assertions. We marker-match on substrings the manifest carries.
+    """
+
+    def __init__(
+        self,
+        responses: dict[str, tuple[int, str]],
+        host_markers: tuple[str, ...] = ("rfc-app", "flotilla", "specs.example"),
+    ):
+        self.responses = responses
+        self.host_markers = host_markers
+        self.calls: list[str] = []
+
+    def __call__(self, request: httpx.Request) -> httpx.Response:
+        url = str(request.url)
+        if any(m in url for m in self.host_markers):
+            self.calls.append(url)
+        for key, (status, body) in self.responses.items():
+            if key in url:
+                return httpx.Response(status, text=body)
+        # Default: 404. Lets tests skip declaring "the rest is 404".
+        return httpx.Response(404, text="not found")
+
+
+@pytest.fixture
+def patched_httpx(monkeypatch, app_with_fake_gitea):  # noqa: F811
+    """Provide a hook the test can call to install a MockTransport.
+
+    M3 note: lifespan now calls `refresh_registry` which hits FakeGitea
+    via the gitea transport. Since `httpx` is a module singleton, installing
+    the docs transport would clobber the FakeGitea mock already installed
+    by `app_with_fake_gitea`. We use a COMPOSITE handler: Gitea API
+    requests (to `http://gitea.test/`) are delegated to FakeGitea; all
+    other requests go to the test-specific handler.
+    """
+    from httpx._client import AsyncClient as RealAsyncClient
+
+    _fake = app_with_fake_gitea[1]
+
+    def install(handler):
+        def composite(request: httpx.Request) -> httpx.Response:
+            if "gitea.test" in str(request.url):
+                return _fake.handle(request)
+            return handler(request)
+
+        def patched(*args, **kwargs):
+            kwargs["transport"] = httpx.MockTransport(composite)
+            return RealAsyncClient(*args, **kwargs)
+
+        monkeypatch.setattr("app.docs_specs.httpx.AsyncClient", patched)
+        return handler
+
+    yield install
+
+
+@pytest.fixture
+def app(app_with_fake_gitea):
+    """Reset the docs-specs cache so cross-test state can't leak."""
+    docs_specs.reset_cache()
+    fastapi_app, _fake = app_with_fake_gitea
+    return fastapi_app
+
+
+# ---------------------------------------------------------------------------
+# Manifest endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_manifest_default(app, monkeypatch):
+    """With `OHM_DOCS_SPECS` unset, the manifest endpoint returns the
+    framework default (rfc-app + flotilla).
+    """
+    monkeypatch.delenv("OHM_DOCS_SPECS", raising=False)
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/manifest")
+        assert r.status_code == 200, r.text
+        payload = r.json()
+        assert "specs" in payload
+        names = [s["name"] for s in payload["specs"]]
+        assert names == ["rfc-app", "flotilla"]
+        # The default URLs point at the OHM-canonical gitea raw paths.
+        assert all("git.wiggleverse.org" in s["url"] for s in payload["specs"])
+
+
+def test_manifest_overridden(app, monkeypatch):
+    """A deployment overriding `OHM_DOCS_SPECS` gets its custom list.
+
+    The manifest is parsed per-request from the env var (no startup
+    binding) so a runtime overlay change is visible without a
+    restart — same shape as the docs_sessions env knobs.
+    """
+    custom = json.dumps(
+        [
+            {
+                "name": "custom-spec",
+                "title": "Custom Spec",
+                "url": "https://specs.example.org/CUSTOM.md",
+            }
+        ]
+    )
+    monkeypatch.setenv("OHM_DOCS_SPECS", custom)
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/manifest")
+        assert r.status_code == 200, r.text
+        payload = r.json()
+        assert payload == {
+            "specs": [
+                {
+                    "name": "custom-spec",
+                    "title": "Custom Spec",
+                    "url": "https://specs.example.org/CUSTOM.md",
+                }
+            ]
+        }
+
+
+def test_manifest_malformed_json_falls_back(app, monkeypatch, caplog):
+    """A non-JSON value in `OHM_DOCS_SPECS` logs a warning and the
+    endpoint falls back to the framework default. Startup is
+    unaffected — the deployment continues to render the spec surface
+    rather than crashing on the typo.
+    """
+    monkeypatch.setenv("OHM_DOCS_SPECS", "{not-json")
+    with caplog.at_level(logging.WARNING, logger="app.docs_specs"):
+        with TestClient(app) as client:
+            r = client.get("/api/docs/specs/manifest")
+            assert r.status_code == 200, r.text
+            payload = r.json()
+            names = [s["name"] for s in payload["specs"]]
+            assert names == ["rfc-app", "flotilla"]
+    assert any(
+        "OHM_DOCS_SPECS is not valid JSON" in rec.message
+        for rec in caplog.records
+    ), f"expected a logged warning; got {[r.message for r in caplog.records]}"
+
+
+def test_manifest_non_list_falls_back(app, monkeypatch, caplog):
+    """`OHM_DOCS_SPECS` must be a JSON array. A JSON object (or any
+    non-list value) falls back to the default + logs a warning.
+    """
+    monkeypatch.setenv("OHM_DOCS_SPECS", json.dumps({"name": "not-a-list"}))
+    with caplog.at_level(logging.WARNING, logger="app.docs_specs"):
+        with TestClient(app) as client:
+            r = client.get("/api/docs/specs/manifest")
+            assert r.status_code == 200, r.text
+            names = [s["name"] for s in r.json()["specs"]]
+            assert names == ["rfc-app", "flotilla"]
+    assert any(
+        "must be a JSON array" in rec.message for rec in caplog.records
+    )
+
+
+def test_manifest_drops_invalid_entry_keeps_valid(app, monkeypatch, caplog):
+    """Per-entry validation: an entry with a bad slug or missing field
+    is dropped; valid entries in the same list are retained.
+    """
+    custom = json.dumps(
+        [
+            {"name": "Bad Slug", "title": "Bad", "url": "https://x"},  # uppercase + space
+            {"name": "..", "title": "Traversal", "url": "https://x"},  # path traversal
+            {"name": "missing-url", "title": "Missing URL"},  # no url
+            {
+                "name": "good-spec",
+                "title": "Good",
+                "url": "https://specs.example.org/GOOD.md",
+            },
+        ]
+    )
+    monkeypatch.setenv("OHM_DOCS_SPECS", custom)
+    with caplog.at_level(logging.WARNING, logger="app.docs_specs"):
+        with TestClient(app) as client:
+            r = client.get("/api/docs/specs/manifest")
+            assert r.status_code == 200, r.text
+            names = [s["name"] for s in r.json()["specs"]]
+            assert names == ["good-spec"]
+    # Three drop warnings (one per bad entry).
+    drops = [r for r in caplog.records if "failed validation" in r.message]
+    assert len(drops) == 3
+
+
+def test_manifest_all_invalid_falls_back(app, monkeypatch, caplog):
+    """If every entry is dropped, the framework default applies (the
+    surface never goes empty due to a bad overlay).
+    """
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps([{"name": "BAD"}, {"name": "..", "title": "x", "url": "y"}]),
+    )
+    with caplog.at_level(logging.WARNING, logger="app.docs_specs"):
+        with TestClient(app) as client:
+            r = client.get("/api/docs/specs/manifest")
+            assert r.status_code == 200, r.text
+            names = [s["name"] for s in r.json()["specs"]]
+            assert names == ["rfc-app", "flotilla"]
+    assert any(
+        "yielded no valid entries" in rec.message for rec in caplog.records
+    )
+
+
+def test_manifest_drops_duplicate_names(app, monkeypatch, caplog):
+    """A duplicate `name` is dropped (the first occurrence wins). The
+    route layer's `/api/docs/specs/{name}` path lookup is by name, so
+    duplicates would otherwise be ambiguous.
+    """
+    custom = json.dumps(
+        [
+            {"name": "x", "title": "First", "url": "https://specs.example/1"},
+            {"name": "x", "title": "Second", "url": "https://specs.example/2"},
+        ]
+    )
+    monkeypatch.setenv("OHM_DOCS_SPECS", custom)
+    with caplog.at_level(logging.WARNING, logger="app.docs_specs"):
+        with TestClient(app) as client:
+            r = client.get("/api/docs/specs/manifest")
+            payload = r.json()
+            assert [s["title"] for s in payload["specs"]] == ["First"]
+    assert any("duplicate name" in rec.message for rec in caplog.records)
+
+
+# ---------------------------------------------------------------------------
+# Spec endpoint — happy + error paths
+# ---------------------------------------------------------------------------
+
+
+def test_spec_happy_path(app, patched_httpx, monkeypatch):
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "rfc-app",
+                    "title": "rfc-app SPEC",
+                    "url": "https://specs.example.org/rfc-app/SPEC.md",
+                }
+            ]
+        ),
+    )
+    body = "# rfc-app SPEC\n\nSection 1...\n"
+    patched_httpx(_UpstreamHandler({"rfc-app/SPEC.md": (200, body)}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/rfc-app")
+        assert r.status_code == 200, r.text
+        assert "text/markdown" in r.headers["content-type"]
+        assert r.text == body
+
+
+def test_spec_upstream_404(app, patched_httpx, monkeypatch):
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "missing-spec",
+                    "title": "Missing",
+                    "url": "https://specs.example.org/missing.md",
+                }
+            ]
+        ),
+    )
+    patched_httpx(_UpstreamHandler({}))  # everything 404s
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/missing-spec")
+        assert r.status_code == 404, r.text
+
+
+def test_spec_upstream_5xx_returns_502(app, patched_httpx, monkeypatch):
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "broken-spec",
+                    "title": "Broken",
+                    "url": "https://specs.example.org/broken.md",
+                }
+            ]
+        ),
+    )
+    patched_httpx(_UpstreamHandler({"broken.md": (500, "internal")}))
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/broken-spec")
+        assert r.status_code == 502, r.text
+        body = r.json()
+        assert body["detail"]["error"] == "specs fetch failed"
+
+
+def test_spec_unknown_name_returns_404(app, patched_httpx, monkeypatch):
+    """A name that doesn't appear in the manifest returns 404 without
+    touching the network. The handler treats "no such configured spec"
+    and "upstream 404" as the same outcome — both render the same
+    "spec not found" empty state on the frontend.
+    """
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "rfc-app",
+                    "title": "rfc-app",
+                    "url": "https://specs.example.org/x.md",
+                }
+            ]
+        ),
+    )
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r = client.get("/api/docs/specs/does-not-exist")
+        assert r.status_code == 404, r.text
+    assert handler.calls == [], "unknown-name lookup must not hit the network"
+
+
+# ---------------------------------------------------------------------------
+# Spec endpoint — slug validation
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.parametrize(
+    "raw_name",
+    [
+        "UPPER",  # uppercase
+        "spaces here",  # whitespace (post-decoding)
+        "with~tilde",  # tilde
+        "with.dot",  # dot
+        "with_under",  # underscore (not allowed by [a-z0-9-]+)
+    ],
+)
+def test_spec_rejects_invalid_name(app, patched_httpx, raw_name):
+    """Names that don't match `^[a-z0-9-]+$` are rejected with 400 at
+    the route layer before any network or cache work.
+
+    Note: `..` is intentionally not in this list because the URL-
+    parsing layer collapses `/api/docs/specs/..` to `/api/docs/specs`
+    before the handler is reached — the path-traversal protection is
+    therefore framework-level (httpx/urllib's path normalizer) rather
+    than route-layer. The slug-validation guard still rejects any
+    `..` that *would* reach the handler (e.g. via an env-configured
+    manifest entry); see `test_manifest_drops_invalid_entry_keeps_valid`
+    for that path.
+    """
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        from urllib.parse import quote
+
+        r = client.get(f"/api/docs/specs/{quote(raw_name, safe='')}")
+        assert r.status_code == 400, r.text
+    assert handler.calls == [], "rejected name must not hit the network"
+
+
+def test_spec_rejects_slash_in_name(app, patched_httpx):
+    """A literal `/` in the path can't make it through the path
+    parameter — FastAPI routes it as a separate segment. The check
+    here is that the request never reaches an upstream fetch.
+    """
+    handler = _UpstreamHandler({})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        # `/api/docs/specs/sub/path` — the second segment makes this
+        # not match the `/{name}` route at all; FastAPI returns 404.
+        r = client.get("/api/docs/specs/sub/path")
+        assert r.status_code == 404, r.text
+    assert handler.calls == [], "non-matching path must not hit the network"
+
+
+# ---------------------------------------------------------------------------
+# Cache behavior
+# ---------------------------------------------------------------------------
+
+
+def test_spec_cache_hits_within_ttl(app, patched_httpx, monkeypatch):
+    monkeypatch.setenv("OHM_DOCS_SPECS_CONTENT_TTL_SEC", "300")
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "rfc-app",
+                    "title": "rfc-app",
+                    "url": "https://specs.example.org/rfc-app/SPEC.md",
+                }
+            ]
+        ),
+    )
+    handler = _UpstreamHandler({"rfc-app/SPEC.md": (200, "# body\n")})
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r1 = client.get("/api/docs/specs/rfc-app")
+        r2 = client.get("/api/docs/specs/rfc-app")
+    assert r1.status_code == 200
+    assert r2.status_code == 200
+    assert len(handler.calls) == 1, (
+        f"expected one upstream call, got {handler.calls}"
+    )
+
+
+def test_spec_404_is_cached(app, patched_httpx, monkeypatch):
+    """Negative caching: a 404 result is cached at the content TTL so
+    a deployment with a misconfigured spec URL doesn't hammer the
+    upstream on every navigation.
+    """
+    monkeypatch.setenv("OHM_DOCS_SPECS_CONTENT_TTL_SEC", "300")
+    monkeypatch.setenv(
+        "OHM_DOCS_SPECS",
+        json.dumps(
+            [
+                {
+                    "name": "missing-spec",
+                    "title": "Missing",
+                    "url": "https://specs.example.org/missing.md",
+                }
+            ]
+        ),
+    )
+    handler = _UpstreamHandler({})  # everything 404s
+    patched_httpx(handler)
+    with TestClient(app) as client:
+        r1 = client.get("/api/docs/specs/missing-spec")
+        r2 = client.get("/api/docs/specs/missing-spec")
+    assert r1.status_code == 404
+    assert r2.status_code == 404
+    assert len(handler.calls) == 1, "negative caching should suppress the 2nd call"

backend/tests/test_e2e_smoke.py

@@ -22,6 +22,7 @@ import pytest
 from test_propose_vertical import (  # noqa: F401
     FakeGitea,
     app_with_fake_gitea,
+    grant_rfc_collaborator,
     provision_user_row,
     sign_in_as,
     tmp_env,
@@ -118,19 +119,25 @@ def test_full_user_lifecycle_propose_through_hygiene(app_with_fake_gitea):
         r = client.post(f"/api/rfcs/ohm/prs/{body_pr}/merge")
         assert r.status_code == 200, r.text
 
-        # --- 7. Graduate the super-draft. ---
+        # --- 7. Graduate the super-draft (in-place flip, §13). ---
         r = client.post(
             "/api/rfcs/ohm/graduate?_sync=1",
-            json={"rfc_id": "RFC-0001", "repo_name": "rfc-0001-ohm",
-                  "owners": ["ben"]},
+            json={"rfc_id": "RFC-0001", "owners": ["ben"]},
         )
         assert r.status_code == 200, r.text
         assert r.json()["succeeded"] is True
         d = client.get("/api/rfcs/ohm").json()
         assert d["state"] == "active"
-        assert d["repo"] == "wiggleverse/rfc-0001-ohm"
+        # Meta-only topology (§1): no per-RFC repo — the active RFC lives
+        # in its meta entry, `repo` stays null.
+        assert d["repo"] is None
 
-        # --- 8. Alice opens a PR on the now-active RFC's per-RFC repo. ---
+        # --- 8. Alice opens a PR on the now-active RFC (meta repo). ---
+        # v0.16.0 (item #12): ben is the RFC owner now; alice needs a
+        # per-RFC contributor invitation to cut a branch. In the
+        # production flow, ben would invite her via /invitations and
+        # she'd accept; we shortcut to the same end-state.
+        grant_rfc_collaborator(user_id=2, rfc_slug="ohm", role_in_rfc="contributor")
         sign_in_as(client, user_id=2, gitea_login="alice",
                    display_name="Alice", role="contributor", email="alice@test")
         r = client.post("/api/rfcs/ohm/branches/main/promote-to-branch", json={})
@@ -194,8 +201,8 @@ def test_full_user_lifecycle_propose_through_hygiene(app_with_fake_gitea):
         )
         assert counters["deleted_post_merge"] >= 1, counters
 
-        # The branch is gone from FakeGitea + cached row flipped.
-        assert active_branch not in fake.branches[("wiggleverse", "rfc-0001-ohm")]
+        # The branch is gone from FakeGitea (meta repo) + cached row flipped.
+        assert active_branch not in fake.branches[("wiggleverse", "meta")]
         cached = db.conn().execute(
             "SELECT state FROM cached_branches WHERE rfc_slug = 'ohm' AND branch_name = ?",
             (active_branch,),
@@ -225,13 +232,17 @@ def test_bounce_webhook_refuses_unsigned_when_secret_configured(app_with_fake_gi
 
         # With the right header, the call passes the guard. (No matching
         # user exists, so we get {matched: False} — that's the v1 contract.)
+        # v0.18.0 Slice 5: the response now includes `correlated_id`
+        # (the outbound_emails row id that matched the bounce's
+        # `message_id`, if one was supplied). The body didn't pass a
+        # message_id, so correlated_id is None.
         r = client.post(
             "/api/webhooks/email-bounce",
             json={"email": "stranger@example.com", "kind": "hard"},
             headers={"X-Webhook-Secret": "shhh"},
         )
         assert r.status_code == 200, r.text
-        assert r.json() == {"ok": True, "matched": False}
+        assert r.json() == {"ok": True, "matched": False, "correlated_id": None}
 
 
 def test_bounce_webhook_open_when_secret_unset(app_with_fake_gitea):

backend/tests/test_email_envelope.py

@@ -0,0 +1,179 @@
+"""Unit tests for `app.email_envelope.build_envelope` (v0.18.0 Slice 1).
+
+These tests don't spin up the FastAPI app or touch the DB — they
+exercise the helper directly. The integration tests in
+test_otc_vertical / test_admin_create_user_invite_vertical /
+test_notifications_vertical exercise the helper's *use* via the
+shared `_SENT` buffer (the send path appends the envelope dict
+before invoking the helper).
+"""
+from __future__ import annotations
+
+from email.utils import parsedate_to_datetime
+
+import pytest
+
+from app.email_envelope import build_envelope
+
+
+def _base_kwargs(**overrides):
+    base = dict(
+        to_address="recipient@example.com",
+        from_address="notifications@ohm.wiggleverse.org",
+        from_name="OHM",
+        subject="A test subject",
+        body_plain="Hello, world.\n",
+    )
+    base.update(overrides)
+    return base
+
+
+# ---------------------------------------------------------------------------
+# Always-present headers
+# ---------------------------------------------------------------------------
+
+
+def test_envelope_sets_from_to_subject():
+    msg = build_envelope(**_base_kwargs())
+    assert msg["To"] == "recipient@example.com"
+    assert msg["Subject"] == "A test subject"
+    # `From` is the display-form: "OHM <notifications@ohm.wiggleverse.org>".
+    assert "OHM" in msg["From"]
+    assert "<notifications@ohm.wiggleverse.org>" in msg["From"]
+
+
+def test_envelope_sets_date_header_parseable():
+    msg = build_envelope(**_base_kwargs())
+    raw = msg["Date"]
+    assert raw, "Date header must be set"
+    # parsedate_to_datetime raises ValueError on malformed input.
+    dt = parsedate_to_datetime(raw)
+    assert dt is not None
+
+
+def test_envelope_sets_message_id_with_from_domain_by_default():
+    msg = build_envelope(**_base_kwargs())
+    mid = msg["Message-ID"]
+    assert mid, "Message-ID must be set"
+    # Shape per RFC 5322 / make_msgid: <random@domain>
+    assert mid.startswith("<") and mid.endswith(">")
+    assert "@ohm.wiggleverse.org>" in mid
+
+
+def test_envelope_message_id_domain_override():
+    msg = build_envelope(**_base_kwargs(msgid_domain="example.test"))
+    assert "@example.test>" in msg["Message-ID"]
+
+
+def test_envelope_message_id_falls_back_to_localhost_if_from_has_no_at():
+    # Defensive: a malformed from_address shouldn't crash the helper.
+    msg = build_envelope(**_base_kwargs(from_address="bare-no-at-sign"))
+    assert "@localhost>" in msg["Message-ID"]
+
+
+# ---------------------------------------------------------------------------
+# Auto-Submitted (RFC 3834)
+# ---------------------------------------------------------------------------
+
+
+def test_envelope_sets_auto_submitted_for_transactional_default():
+    msg = build_envelope(**_base_kwargs())
+    assert msg["Auto-Submitted"] == "auto-generated"
+
+
+def test_envelope_omits_auto_submitted_when_transactional_is_false():
+    msg = build_envelope(**_base_kwargs(is_transactional=False))
+    assert msg["Auto-Submitted"] is None
+
+
+# ---------------------------------------------------------------------------
+# Reply-To
+# ---------------------------------------------------------------------------
+
+
+def test_envelope_sets_reply_to_when_provided():
+    msg = build_envelope(**_base_kwargs(reply_to="ohm@wiggleverse.org"))
+    assert msg["Reply-To"] == "ohm@wiggleverse.org"
+
+
+def test_envelope_omits_reply_to_when_absent():
+    msg = build_envelope(**_base_kwargs())
+    assert msg["Reply-To"] is None
+
+
+# ---------------------------------------------------------------------------
+# List-Unsubscribe (the headers RFC 8058 / Gmail-Yahoo care about)
+# ---------------------------------------------------------------------------
+
+
+def test_envelope_no_list_unsubscribe_when_neither_given():
+    """OTC mail: the recipient explicitly requested the code; no
+    unsubscribe semantics. The header MUST be absent (presence would
+    imply OHM has the recipient on a list, which it doesn't)."""
+    msg = build_envelope(**_base_kwargs())
+    assert msg["List-Unsubscribe"] is None
+    assert msg["List-Unsubscribe-Post"] is None
+
+
+def test_envelope_mailto_only_list_unsubscribe():
+    """Admin invite / per-RFC invite: `mailto:` form only, no URL.
+    The recipient isn't a user yet, so there's no per-user opt-out
+    URL to flip; the operator handles ad-hoc opt-outs manually."""
+    msg = build_envelope(**_base_kwargs(
+        unsubscribe_mailto="ohm@wiggleverse.org?subject=remove",
+    ))
+    assert msg["List-Unsubscribe"] == "<mailto:ohm@wiggleverse.org?subject=remove>"
+    # NO List-Unsubscribe-Post when only a mailto is present — the
+    # one-click semantic requires a URL the MUA can POST to.
+    assert msg["List-Unsubscribe-Post"] is None
+
+
+def test_envelope_full_one_click_list_unsubscribe():
+    """Watcher notification / bundle: `mailto:` + signed-URL +
+    `List-Unsubscribe-Post: List-Unsubscribe=One-Click`. Gmail and
+    Yahoo enforce this for bulk-adjacent mail per RFC 8058."""
+    msg = build_envelope(**_base_kwargs(
+        unsubscribe_mailto="ohm@wiggleverse.org?subject=remove",
+        unsubscribe_url="https://ohm.wiggleverse.org/api/email/unsubscribe?t=abc",
+    ))
+    lu = msg["List-Unsubscribe"]
+    assert "<mailto:ohm@wiggleverse.org?subject=remove>" in lu
+    assert "<https://ohm.wiggleverse.org/api/email/unsubscribe?t=abc>" in lu
+    assert msg["List-Unsubscribe-Post"] == "List-Unsubscribe=One-Click"
+
+
+def test_envelope_url_only_list_unsubscribe_still_sets_post():
+    msg = build_envelope(**_base_kwargs(
+        unsubscribe_url="https://ohm.wiggleverse.org/api/email/unsubscribe?t=abc",
+    ))
+    assert msg["List-Unsubscribe"] == "<https://ohm.wiggleverse.org/api/email/unsubscribe?t=abc>"
+    assert msg["List-Unsubscribe-Post"] == "List-Unsubscribe=One-Click"
+
+
+# ---------------------------------------------------------------------------
+# Body shape — plain-only vs multipart/alternative
+# ---------------------------------------------------------------------------
+
+
+def test_envelope_plain_only_body_is_text_plain():
+    msg = build_envelope(**_base_kwargs())
+    # No HTML alternative -> single-part text/plain.
+    assert msg.get_content_type() == "text/plain"
+    assert msg.get_content().strip() == "Hello, world."
+
+
+def test_envelope_html_body_is_guarded_not_enabled():
+    # I3 (security-audit-0026): the HTML/multipart-alternative path is
+    # intentionally not enabled — passing body_html must fail loudly so
+    # a future caller can't silently ship unescaped user HTML (the C1
+    # stored-XSS class in the mail channel). When HTML mail is enabled
+    # deliberately, this test flips to assert the multipart shape.
+    with pytest.raises(NotImplementedError):
+        build_envelope(**_base_kwargs(body_html="<p>Hello, <b>world</b>.</p>"))
+
+
+def test_envelope_html_none_is_plain_only():
+    # The guard keys on `is not None`, so the default (None) stays the
+    # live plain-text path — exercised here to lock the boundary.
+    msg = build_envelope(**_base_kwargs(body_html=None))
+    assert msg.get_content_type() == "text/plain"

backend/tests/test_entry_review_fields.py

@@ -0,0 +1,42 @@
+"""§22.4c — the unreviewed/reviewed_at/reviewed_by entry frontmatter fields."""
+from __future__ import annotations
+
+from app import entry as entry_mod
+
+
+def test_parse_defaults_unreviewed_false_when_absent():
+    text = "---\nslug: ohm\ntitle: OHM\nstate: active\n---\n\nBody.\n"
+    e = entry_mod.parse(text)
+    assert e.unreviewed is False
+    assert e.reviewed_at is None
+    assert e.reviewed_by is None
+
+
+def test_parse_reads_review_fields():
+    text = (
+        "---\nslug: ohm\ntitle: OHM\nstate: active\n"
+        "unreviewed: true\nreviewed_at: '2026-06-03'\nreviewed_by: ben\n---\n\nBody.\n"
+    )
+    e = entry_mod.parse(text)
+    assert e.unreviewed is True
+    assert e.reviewed_at == "2026-06-03"
+    assert e.reviewed_by == "ben"
+
+
+def test_serialize_emits_review_fields_only_when_meaningful():
+    e = entry_mod.Entry(slug="a", title="A", state="super-draft")
+    assert "unreviewed" not in entry_mod.serialize(e)
+    assert "reviewed_at" not in entry_mod.serialize(e)
+    e2 = entry_mod.Entry(slug="b", title="B", state="active", unreviewed=True)
+    assert "unreviewed: true" in entry_mod.serialize(e2)
+
+
+def test_round_trip_preserves_review_fields():
+    e = entry_mod.Entry(
+        slug="b", title="B", state="active",
+        unreviewed=False, reviewed_at="2026-06-03", reviewed_by="ben",
+    )
+    back = entry_mod.parse(entry_mod.serialize(e))
+    assert back.reviewed_at == "2026-06-03"
+    assert back.reviewed_by == "ben"
+    assert back.unreviewed is False

backend/tests/test_graduation_vertical.py

@@ -1,29 +1,29 @@
-"""End-to-end integration tests for the Slice 5 vertical (§13 in full).
+"""End-to-end integration tests for the §13 graduation flow under the
+meta-only topology (SPEC §1, ROADMAP #36).
 
-Walks the §13.3 transactional sequence end-to-end against the in-process
-FakeGitea from test_propose_vertical.py:
+Graduation is an in-place state flip on the meta entry — no per-RFC repo
+is created, the body is kept, and there is no multi-step transaction or
+rollback (§13.3). These tests walk it against the in-process FakeGitea
+from test_propose_vertical.py:
 
-  * Seed an owned super-draft (skipping the propose+merge + §13.1 claim
-    round-trips already proven by Slice 1 and exercised in
-    test_claim_opens_meta_pr below for the §13.1 surface itself).
+  * Seed an owned super-draft (the §13.1 claim flow is exercised
+    separately in test_claim_opens_meta_pr).
   * GET /api/rfcs/<slug>/graduate/check returns per-field validity for
-    the dialog.
-  * GET /api/rfcs/<slug>/blocking-prs returns the §9.8 precondition list.
-  * POST /api/rfcs/<slug>/graduate?_sync=1 runs the five-step sequence
-    inline. On success: per-RFC repo exists with RFC.md / README.md /
-    .rfc/metadata.yaml, meta-entry body is stripped, frontmatter is
-    graduated, cached_rfcs.state is 'active'.
-  * §9.8 precondition gate refuses the start when a body-edit PR is open.
-  * Rollback on a mid-sequence failure unwinds repo creation cleanly.
-  * §13.4 chat migration: whole-doc threads under (slug, 'main') survive
-    graduation unchanged — the rfc_slug is the canonical key per §2.3,
-    so no data movement is needed.
-  * §9.8 pre-graduation history: the new RFC's /main response surfaces
-    edit-branch threads under `pre_graduation_history`.
+    the two-field dialog (integer id + owners; no repo name).
+  * POST /api/rfcs/<slug>/graduate?_sync=1 opens + merges the flip PR
+    inline. On success: NO per-RFC repo, the meta entry is `state:
+    active` with the body KEPT and `repo` null, cached_rfcs.state flips
+    to 'active'.
+  * An open body-edit PR no longer blocks graduation (§9.8) — they
+    coexist.
+  * An open-PR failure leaves the entry a super-draft (nothing created);
+    a merge failure cleans up the half-open PR/branch and leaves the
+    entry a super-draft.
+  * §13.4: chat threads + edit branches stay put — the slug is the
+    canonical key per §2.3, so nothing moves at the flip.
 
-The orchestrator's `?_sync=1` seam awaits the sequence inline so the
-test can assert post-conditions on the same event loop tick. Production
-clients use the spec-described SSE shape via `/graduate/progress`.
+The orchestrator's `?_sync=1` seam awaits the flip inline so the test can
+assert post-conditions on the same event loop tick.
 """
 from __future__ import annotations
 
@@ -34,6 +34,7 @@ import pytest
 from test_propose_vertical import (  # noqa: F401
     FakeGitea,
     app_with_fake_gitea,
+    grant_rfc_collaborator,
     provision_user_row,
     sign_in_as,
     tmp_env,
@@ -109,7 +110,9 @@ def seed_owned_super_draft(fake: FakeGitea, *, slug: str, title: str, pitch: str
 # ---------------------------------------------------------------------------
 
 
-def test_graduate_check_validates_three_fields(app_with_fake_gitea):
+def test_graduate_check_validates_id_and_owners(app_with_fake_gitea):
+    """Two-field dialog under meta-only: integer id + owners. No repo
+    name to validate (§13.2)."""
     from fastapi.testclient import TestClient
 
     app, fake = app_with_fake_gitea
@@ -120,57 +123,46 @@ def test_graduate_check_validates_three_fields(app_with_fake_gitea):
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
 
-        # Happy: a fresh RFC-0001 + rfc-0001-ohm repo name.
-        r = client.get("/api/rfcs/ohm/graduate/check",
-                       params={"id": "RFC-0001", "repo": "rfc-0001-ohm"})
+        # Happy: a fresh RFC-0001.
+        r = client.get("/api/rfcs/ohm/graduate/check", params={"id": "RFC-0001"})
         assert r.status_code == 200, r.text
         d = r.json()
         assert d["id"]["ok"] is True
-        assert d["repo"]["ok"] is True
         assert d["owners"]["ok"] is True
-        assert d["blocking_prs"]["ok"] is True
         assert d["can_submit"] is True
+        # No repo field in the meta-only check response.
+        assert "repo" not in d
 
         # ID format error — non-numeric tail.
-        r = client.get("/api/rfcs/ohm/graduate/check",
-                       params={"id": "RFC-abcd", "repo": "rfc-0001-ohm"})
+        r = client.get("/api/rfcs/ohm/graduate/check", params={"id": "RFC-abcd"})
         d = r.json()
         assert d["id"]["ok"] is False
         assert d["can_submit"] is False
 
-        # Repo name pattern error — leading dot.
-        r = client.get("/api/rfcs/ohm/graduate/check",
-                       params={"id": "RFC-0001", "repo": ".bad"})
-        d = r.json()
-        assert d["repo"]["ok"] is False
-
 
 def test_graduate_check_refuses_when_no_owners(app_with_fake_gitea):
     """An unclaimed super-draft fails the owners precondition; can_submit
-    flips false even with valid id+repo."""
+    flips false even with a valid id."""
     from fastapi.testclient import TestClient
 
     app, fake = app_with_fake_gitea
     with TestClient(app) as client:
         provision_user_row(user_id=1, login="ben", role="owner")
-        # No owners — simulates an unclaimed super-draft.
         seed_owned_super_draft(fake, slug="ohm", title="OHM", pitch=PITCH, owners=[])
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
-        r = client.get("/api/rfcs/ohm/graduate/check",
-                       params={"id": "RFC-0001", "repo": "rfc-0001-ohm"})
+        r = client.get("/api/rfcs/ohm/graduate/check", params={"id": "RFC-0001"})
         d = r.json()
         assert d["owners"]["ok"] is False
         assert "No owners" in d["owners"]["error"]
         assert d["can_submit"] is False
 
 
-def test_graduate_happy_path_runs_five_steps_and_flips_state(app_with_fake_gitea):
-    """The full §13.3 sequence: create repo, seed files, open PR, merge
-    PR, refresh cache. End state: cached_rfcs.state='active', the meta
-    entry's body is stripped, the per-RFC repo has RFC.md, the audit
-    log carries graduate_start → graduate_complete bracketing the
-    per-step rows."""
+def test_graduate_happy_path_flips_in_place_keeping_body(app_with_fake_gitea):
+    """The meta-only flip: open + merge a frontmatter PR. End state:
+    cached_rfcs.state='active', the meta entry's body is KEPT, `repo` is
+    null, NO per-RFC repo exists, and the audit log carries graduate_start
+    → graduate_pr_open → graduate_pr_merge → graduate_complete."""
     from fastapi.testclient import TestClient
     from app import db, entry as entry_mod
 
@@ -185,60 +177,57 @@ def test_graduate_happy_path_runs_five_steps_and_flips_state(app_with_fake_gitea
 
         r = client.post(
             "/api/rfcs/ohm/graduate?_sync=1",
-            json={"rfc_id": "RFC-0042", "repo_name": "rfc-0042-ohm",
-                  "owners": ["ben"]},
+            json={"rfc_id": "RFC-0042", "owners": ["ben"]},
         )
         assert r.status_code == 200, r.text
         d = r.json()
         assert d["finished"] is True
         assert d["succeeded"] is True
-        assert d["repo"] == "wiggleverse/rfc-0042-ohm"
+        # No repo in the response, no per-RFC repo on Gitea.
+        assert "repo" not in d
+        assert ("wiggleverse", "rfc-0042-ohm") not in fake.repos
+        assert not any(
+            k[1].startswith("rfc-0042") for k in fake.repos
+        ), f"a per-RFC repo was created: {fake.repos}"
 
-        # 1. Per-RFC repo exists on Gitea.
-        assert ("wiggleverse", "rfc-0042-ohm") in fake.repos
-        # 2. Seed files landed on main.
-        assert ("wiggleverse", "rfc-0042-ohm", "main", "RFC.md") in fake.files
-        assert ("wiggleverse", "rfc-0042-ohm", "main", "README.md") in fake.files
-        assert ("wiggleverse", "rfc-0042-ohm", "main", ".rfc/metadata.yaml") in fake.files
-        rfc_md = fake.files[("wiggleverse", "rfc-0042-ohm", "main", "RFC.md")]["content"]
-        assert "Open Human Model is a framework" in rfc_md
-        # 3. Meta entry body is stripped + frontmatter graduated.
+        # Meta entry on main: state flipped, body KEPT, repo null.
         meta_text = fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
         graduated = entry_mod.parse(meta_text)
         assert graduated.state == "active"
         assert graduated.id == "RFC-0042"
-        assert graduated.repo == "wiggleverse/rfc-0042-ohm"
+        assert graduated.repo is None
         assert graduated.graduated_by == "ben"
         assert graduated.graduated_at  # non-empty ISO date
-        assert graduated.body.strip() == ""
-        # 5. cached_rfcs.state flipped to active via the inline refresh.
+        assert "Open Human Model is a framework" in graduated.body
+
+        # cached_rfcs flipped to active via the inline refresh; body intact.
         cached = db.conn().execute(
             "SELECT state, rfc_id, repo, body FROM cached_rfcs WHERE slug = 'ohm'"
         ).fetchone()
         assert cached["state"] == "active"
         assert cached["rfc_id"] == "RFC-0042"
-        assert cached["repo"] == "wiggleverse/rfc-0042-ohm"
-        # cached body now mirrors RFC.md from the per-RFC repo.
+        assert cached["repo"] is None
         assert "Open Human Model is a framework" in cached["body"]
 
-        # Audit log: graduate_start, graduate_repo_create, graduate_repo_seed,
-        # graduate_pr_open, graduate_pr_merge, graduate_complete, in order.
         kinds = [
-            r["action_kind"]
-            for r in db.conn().execute(
+            row["action_kind"]
+            for row in db.conn().execute(
                 "SELECT action_kind FROM actions WHERE rfc_slug = 'ohm' ORDER BY id"
             )
         ]
-        for needed in ("graduate_start", "graduate_repo_create",
-                       "graduate_repo_seed", "graduate_pr_open",
+        for needed in ("graduate_start", "graduate_pr_open",
                        "graduate_pr_merge", "graduate_complete"):
             assert needed in kinds, f"missing audit row {needed}: {kinds}"
+        # The retired per-repo steps must NOT appear.
+        for gone in ("graduate_repo_create", "graduate_repo_seed",
+                     "graduate_repo_delete", "graduate_rollback"):
+            assert gone not in kinds, f"retired audit row present: {gone}"
 
 
-def test_graduate_refuses_when_body_edit_pr_open(app_with_fake_gitea):
-    """§9.8: an open meta-repo body-edit PR against rfcs/<slug>.md blocks
-    graduation before the bot starts the sequence — §13.3's rollback
-    complexity does not grow."""
+def test_graduate_coexists_with_open_body_edit_pr(app_with_fake_gitea):
+    """§9.8 (meta-only): an open meta-repo body-edit PR no longer blocks
+    graduation — the body is kept, so they coexist. /check stays
+    submittable and the flip succeeds."""
     from fastapi.testclient import TestClient
     from app import db
 
@@ -248,10 +237,11 @@ def test_graduate_refuses_when_body_edit_pr_open(app_with_fake_gitea):
         provision_user_row(user_id=2, login="alice", role="contributor")
         seed_owned_super_draft(fake, slug="ohm", title="OHM",
                                pitch=PITCH, owners=["ben"])
+        grant_rfc_collaborator(user_id=2, rfc_slug="ohm", role_in_rfc="contributor")
         sign_in_as(client, user_id=2, gitea_login="alice",
                    display_name="Alice", role="contributor")
 
-        # Cut an edit branch and open a body-edit PR (full Slice 4 path).
+        # Cut an edit branch and open a body-edit PR.
         branch = client.post("/api/rfcs/ohm/start-edit-branch", json={}).json()["branch_name"]
         view = client.get(f"/api/rfcs/ohm/branches/{branch}").json()
         thread_id = view["main_thread_id"]
@@ -275,94 +265,31 @@ def test_graduate_refuses_when_body_edit_pr_open(app_with_fake_gitea):
             f"/api/rfcs/ohm/branches/{branch}/open-pr",
             json={"title": "Add harm", "description": "Adds harm dimension."},
         ).json()["pr_number"]
+        assert pr_number  # PR is open
 
-        # /blocking-prs surfaces it.
+        # /check stays submittable despite the open body-edit PR.
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
-        r = client.get("/api/rfcs/ohm/blocking-prs")
-        items = r.json()["items"]
-        assert len(items) == 1
-        assert items[0]["pr_number"] == pr_number
+        d = client.get("/api/rfcs/ohm/graduate/check", params={"id": "RFC-0001"}).json()
+        assert "blocking_prs" not in d
+        assert d["can_submit"] is True
 
-        # /check refuses can_submit.
-        r = client.get("/api/rfcs/ohm/graduate/check",
-                       params={"id": "RFC-0001", "repo": "rfc-0001-ohm"})
-        d = r.json()
-        assert d["blocking_prs"]["ok"] is False
-        assert d["can_submit"] is False
-
-        # POST refuses with 409 — the bot never starts the sequence.
+        # The flip succeeds — coexists with the open body-edit PR.
         r = client.post(
             "/api/rfcs/ohm/graduate?_sync=1",
-            json={"rfc_id": "RFC-0001", "repo_name": "rfc-0001-ohm",
-                  "owners": ["ben"]},
+            json={"rfc_id": "RFC-0001", "owners": ["ben"]},
         )
-        assert r.status_code == 409
-        assert "blocking graduation" in r.text or "block" in r.text
-
-
-def test_graduate_rollback_on_step_2_seed_failure(app_with_fake_gitea):
-    """Step 2 (seed files) fails partway → the orchestrator rolls back
-    step 1 (delete the repo) and records the rollback in the audit log.
-    The cached_rfcs row stays at 'super-draft'."""
-    from fastapi.testclient import TestClient
-    from app import db
-    from app.bot import Bot
-    from app.gitea import Gitea, GiteaError
-
-    app, fake = app_with_fake_gitea
-    with TestClient(app) as client:
-        provision_user_row(user_id=1, login="ben", role="owner")
-        seed_owned_super_draft(fake, slug="ohm", title="OHM",
-                               pitch=PITCH, owners=["ben"])
-        sign_in_as(client, user_id=1, gitea_login="ben",
-                   display_name="Ben", role="owner")
-
-        # Monkey-patch the bot to fail on seed_graduated_rfc. The repo
-        # has already been created in step 1; the rollback must delete it.
-        orig_seed = Bot.seed_graduated_rfc
-        async def boom(self, *args, **kwargs):
-            raise GiteaError(500, "simulated seed failure for rollback test")
-        Bot.seed_graduated_rfc = boom
-        try:
-            r = client.post(
-                "/api/rfcs/ohm/graduate?_sync=1",
-                json={"rfc_id": "RFC-0003", "repo_name": "rfc-0003-ohm",
-                      "owners": ["ben"]},
-            )
-        finally:
-            Bot.seed_graduated_rfc = orig_seed
         assert r.status_code == 200, r.text
-        d = r.json()
-        assert d["finished"] is True
-        assert d["succeeded"] is False
-
-        # Repo deleted as the rollback inverse.
-        assert ("wiggleverse", "rfc-0003-ohm") not in fake.repos
-        # Meta entry unchanged.
+        assert r.json()["succeeded"] is True
         cached = db.conn().execute(
-            "SELECT state, rfc_id FROM cached_rfcs WHERE slug = 'ohm'"
+            "SELECT state FROM cached_rfcs WHERE slug = 'ohm'"
         ).fetchone()
-        assert cached["state"] == "super-draft"
-        assert cached["rfc_id"] is None
-        # Audit log carries the rollback row.
-        kinds = [
-            r["action_kind"]
-            for r in db.conn().execute(
-                "SELECT action_kind FROM actions WHERE rfc_slug = 'ohm' ORDER BY id"
-            )
-        ]
-        assert "graduate_start" in kinds
-        assert "graduate_repo_create" in kinds
-        assert "graduate_repo_delete" in kinds
-        assert "graduate_rollback" in kinds
-        assert "graduate_complete" not in kinds
+        assert cached["state"] == "active"
 
 
-def test_graduate_rollback_on_step_3_pr_open_failure(app_with_fake_gitea):
-    """Step 3 (open PR) fails → the orchestrator rolls back steps 2 and
-    1 (deleting the repo, which reclaims the seed commits at the same
-    time). The meta-repo entry is untouched."""
+def test_graduate_open_pr_failure_leaves_super_draft(app_with_fake_gitea):
+    """An open-PR failure creates nothing — the entry stays a super-draft
+    with its body intact and no graduation PR on the meta repo."""
     from fastapi.testclient import TestClient
     from app import db
     from app.bot import Bot
@@ -383,19 +310,92 @@ def test_graduate_rollback_on_step_3_pr_open_failure(app_with_fake_gitea):
         try:
             r = client.post(
                 "/api/rfcs/ohm/graduate?_sync=1",
-                json={"rfc_id": "RFC-0007", "repo_name": "rfc-0007-ohm",
-                      "owners": ["ben"]},
+                json={"rfc_id": "RFC-0007", "owners": ["ben"]},
             )
         finally:
             Bot.open_graduation_pr = orig_open_pr
         assert r.status_code == 200, r.text
         assert r.json()["succeeded"] is False
-        # Repo torn down.
-        assert ("wiggleverse", "rfc-0007-ohm") not in fake.repos
-        # Meta entry's body still has the pitch (not stripped).
+
+        # Entry untouched: still super-draft, body intact on main.
+        cached = db.conn().execute(
+            "SELECT state, rfc_id FROM cached_rfcs WHERE slug = 'ohm'"
+        ).fetchone()
+        assert cached["state"] == "super-draft"
+        assert cached["rfc_id"] is None
         meta_text = fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
         assert "Open Human Model is a framework" in meta_text
 
+        kinds = [
+            row["action_kind"]
+            for row in db.conn().execute(
+                "SELECT action_kind FROM actions WHERE rfc_slug = 'ohm' ORDER BY id"
+            )
+        ]
+        assert "graduate_start" in kinds
+        assert "graduate_failed" in kinds
+        assert "graduate_complete" not in kinds
+
+
+def test_graduate_merge_failure_cleans_up_pr(app_with_fake_gitea):
+    """A merge failure leaves the flip PR open on its dash-suffixed
+    branch; the orchestrator closes the PR and deletes the branch so
+    failed attempts don't accumulate. The entry stays a super-draft —
+    the flip PR's commit was on a branch, not on main."""
+    from fastapi.testclient import TestClient
+    from app import db
+    from app.bot import Bot
+    from app.gitea import GiteaError
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["ben"])
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner")
+
+        orig_merge = Bot.merge_graduation_pr
+        async def boom(self, *args, **kwargs):
+            raise GiteaError(502, "simulated merge failure")
+        Bot.merge_graduation_pr = boom
+        try:
+            r = client.post(
+                "/api/rfcs/ohm/graduate?_sync=1",
+                json={"rfc_id": "RFC-0009", "owners": ["ben"]},
+            )
+        finally:
+            Bot.merge_graduation_pr = orig_merge
+        assert r.status_code == 200, r.text
+        assert r.json()["succeeded"] is False
+
+        # Entry stays super-draft on main (the flip never merged).
+        cached = db.conn().execute(
+            "SELECT state FROM cached_rfcs WHERE slug = 'ohm'"
+        ).fetchone()
+        assert cached["state"] == "super-draft"
+        meta_text = fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
+        assert "state: super-draft" in meta_text
+
+        # The dash-suffixed graduation branch was cleaned up.
+        grad_branches = [
+            name for (o, repo), branches in fake.branches.items()
+            if (o, repo) == ("wiggleverse", "meta")
+            for name in branches
+            if name.startswith("graduate-ohm-")
+        ]
+        assert grad_branches == [], f"leftover graduation branch: {grad_branches}"
+
+        kinds = [
+            row["action_kind"]
+            for row in db.conn().execute(
+                "SELECT action_kind FROM actions WHERE rfc_slug = 'ohm' ORDER BY id"
+            )
+        ]
+        assert "graduate_pr_open" in kinds
+        assert "graduate_failed" in kinds
+        assert "graduate_complete" not in kinds
+
 
 def test_graduate_refuses_concurrent_graduation(app_with_fake_gitea):
     """A second graduation request for a slug already in-flight is refused."""
@@ -410,17 +410,14 @@ def test_graduate_refuses_concurrent_graduation(app_with_fake_gitea):
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
 
-        # Seed a synthetic in-flight state so the registry refuses the second.
         st = api_graduation._new_active(
-            "ohm", rfc_id="RFC-0001", repo_name="rfc-0001-ohm",
-            repo_full="wiggleverse/rfc-0001-ohm", owners=["ben"], arbiters=["ben"],
+            "ohm", rfc_id="RFC-0001", owners=["ben"], arbiters=["ben"],
         )
         st.finished = False
         try:
             r = client.post(
                 "/api/rfcs/ohm/graduate?_sync=1",
-                json={"rfc_id": "RFC-0001", "repo_name": "rfc-0001-ohm",
-                      "owners": ["ben"]},
+                json={"rfc_id": "RFC-0001", "owners": ["ben"]},
             )
             assert r.status_code == 409
         finally:
@@ -428,11 +425,9 @@ def test_graduate_refuses_concurrent_graduation(app_with_fake_gitea):
 
 
 def test_chat_threads_survive_graduation_without_data_movement(app_with_fake_gitea):
-    """§13.4: chat threads on the super-draft's canonical-body view
-    (`branch_name='main'`) are interpreted as the new RFC's main-thread
-    after graduation. The rows don't move — the rfc_slug is canonical
-    per §2.3 — so the same thread surfaces from both before and after
-    the graduation."""
+    """§13.4: chat threads on the entry's main view (`branch_name='main'`)
+    stay put across the flip — the rfc_slug is canonical per §2.3 — so the
+    same thread surfaces from /branches/main before and after graduation."""
     from fastapi.testclient import TestClient
     from app import db
 
@@ -444,9 +439,6 @@ def test_chat_threads_survive_graduation_without_data_movement(app_with_fake_git
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
 
-        # Materialize a whole-doc main thread + a message on it. This
-        # mirrors what reading the canonical-body view would create
-        # lazily (§8.12 / api_branches._ensure_branch_chat_thread).
         cur = db.conn().execute(
             """
             INSERT INTO threads (rfc_slug, branch_name, anchor_kind, thread_kind, created_by)
@@ -462,32 +454,26 @@ def test_chat_threads_survive_graduation_without_data_movement(app_with_fake_git
             (thread_id,),
         )
 
-        # Graduate.
         r = client.post(
             "/api/rfcs/ohm/graduate?_sync=1",
-            json={"rfc_id": "RFC-0099", "repo_name": "rfc-0099-ohm",
-                  "owners": ["ben"]},
+            json={"rfc_id": "RFC-0099", "owners": ["ben"]},
         )
         assert r.status_code == 200, r.text
 
-        # The thread row's identity is unchanged.
         row = db.conn().execute(
             "SELECT id, branch_name FROM threads WHERE id = ?", (thread_id,),
         ).fetchone()
         assert row["branch_name"] == "main"
-        # The new RFC's main view surfaces the same thread id as its
-        # whole-doc main thread (the entry is now active, the branch
-        # 'main' now points at the per-RFC repo's main, but the
-        # `(rfc_slug, branch_name)` key remains the canonical anchor).
         r = client.get("/api/rfcs/ohm/branches/main")
         assert r.status_code == 200, r.text
         assert r.json()["main_thread_id"] == thread_id
 
 
-def test_pre_graduation_history_surfaces_edit_branch_threads(app_with_fake_gitea):
-    """§9.8: after graduation, threads on meta-repo edit branches stay
-    attached to their original branch_name and surface from the new
-    RFC's /main response under `pre_graduation_history`."""
+def test_edit_branch_surfaces_normally_after_graduation(app_with_fake_gitea):
+    """§13.4 (meta-only): after graduation an edit branch is a *current*
+    branch of the now-active RFC — it surfaces in the normal `branches`
+    list, and there is no separate `pre_graduation_history` set (that
+    affordance is legacy per-repo only)."""
     from fastapi.testclient import TestClient
     from app import db
 
@@ -497,8 +483,8 @@ def test_pre_graduation_history_surfaces_edit_branch_threads(app_with_fake_gitea
         provision_user_row(user_id=2, login="alice", role="contributor")
         seed_owned_super_draft(fake, slug="ohm", title="OHM",
                                pitch=PITCH, owners=["ben"])
+        grant_rfc_collaborator(user_id=2, rfc_slug="ohm", role_in_rfc="contributor")
 
-        # Alice cuts an edit branch and starts chatting on it.
         sign_in_as(client, user_id=2, gitea_login="alice",
                    display_name="Alice", role="contributor")
         branch = client.post("/api/rfcs/ohm/start-edit-branch", json={}).json()["branch_name"]
@@ -507,30 +493,139 @@ def test_pre_graduation_history_surfaces_edit_branch_threads(app_with_fake_gitea
         db.conn().execute(
             """
             INSERT INTO thread_messages (thread_id, role, author_user_id, text)
-            VALUES (?, 'user', 2, 'pre-graduation note on an edit branch')
+            VALUES (?, 'user', 2, 'note on an edit branch')
             """,
             (thread_id,),
         )
 
-        # Ben graduates.
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
         r = client.post(
             "/api/rfcs/ohm/graduate?_sync=1",
-            json={"rfc_id": "RFC-0100", "repo_name": "rfc-0100-ohm",
-                  "owners": ["ben"]},
+            json={"rfc_id": "RFC-0100", "owners": ["ben"]},
         )
         assert r.status_code == 200, r.text
 
-        # /main on the now-active RFC surfaces the pre-graduation history.
-        r = client.get("/api/rfcs/ohm/main")
-        d = r.json()
+        d = client.get("/api/rfcs/ohm/main").json()
         assert d["state"] == "active"
-        hist = d["pre_graduation_history"]
-        assert len(hist) >= 1
-        assert any(h["branch_name"] == branch for h in hist)
-        target = next(h for h in hist if h["branch_name"] == branch)
-        assert target["message_count"] >= 1
+        # The edit branch is a current branch; no pre-graduation hop.
+        assert d["pre_graduation_history"] == []
+        assert any(b["name"] == branch for b in d["branches"]), \
+            f"edit branch not in branches: {[b['name'] for b in d['branches']]}"
+
+
+def test_graduate_check_accepts_blank_id(app_with_fake_gitea):
+    """§13.2 (optional number): a blank id is VALID — it means "graduate
+    without a number." `can_submit` stays true (owners are set), and an
+    absent `id` param behaves the same as an explicit empty string."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM", pitch=PITCH, owners=["ben"])
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner")
+
+        # Explicit empty id.
+        d = client.get("/api/rfcs/ohm/graduate/check", params={"id": ""}).json()
+        assert d["id"]["ok"] is True
+        assert d["id"]["error"] is None
+        assert d["can_submit"] is True
+
+        # No id param at all — same default-accepted shape.
+        d = client.get("/api/rfcs/ohm/graduate/check").json()
+        assert d["id"]["ok"] is True
+        assert d["can_submit"] is True
+
+        # A malformed (non-blank) id is still rejected.
+        d = client.get("/api/rfcs/ohm/graduate/check", params={"id": "RFC-xx"}).json()
+        assert d["id"]["ok"] is False
+        assert d["can_submit"] is False
+
+
+def test_graduate_without_number_flips_to_active_null_id_by_slug(app_with_fake_gitea):
+    """§13.2/§13.3 (optional number): graduating with a blank id flips the
+    entry to `active` with `id: null`. The slug is the canonical identifier;
+    the catalog shows the entry as active with no number, and the audit row
+    records rfc_id null."""
+    from fastapi.testclient import TestClient
+    from app import db, entry as entry_mod
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        seed_owned_super_draft(fake, slug="ohm", title="Open Human Model",
+                               pitch=PITCH, owners=["ben"], arbiters=["ben"])
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner", email="ben@test")
+
+        # Blank rfc_id → graduate without a number.
+        r = client.post(
+            "/api/rfcs/ohm/graduate?_sync=1",
+            json={"rfc_id": "", "owners": ["ben"]},
+        )
+        assert r.status_code == 200, r.text
+        d = r.json()
+        assert d["succeeded"] is True
+        assert d["rfc_id"] is None
+
+        # Meta entry: active, id null, body kept, graduation stamped.
+        meta_text = fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
+        graduated = entry_mod.parse(meta_text)
+        assert graduated.state == "active"
+        assert graduated.id is None
+        assert graduated.graduated_by == "ben"
+        assert graduated.graduated_at
+        assert "Open Human Model is a framework" in graduated.body
+
+        # Cache flipped to active with a null rfc_id.
+        cached = db.conn().execute(
+            "SELECT state, rfc_id FROM cached_rfcs WHERE slug = 'ohm'"
+        ).fetchone()
+        assert cached["state"] == "active"
+        assert cached["rfc_id"] is None
+
+        # Catalog: present as active, identified by slug (no number).
+        items = client.get("/api/rfcs").json()["items"]
+        ohm = next(i for i in items if i["slug"] == "ohm")
+        assert ohm["state"] == "active"
+        assert ohm["id"] is None
+
+        # Audit: graduate_complete with rfc_id null.
+        complete = db.conn().execute(
+            """
+            SELECT details FROM actions
+             WHERE rfc_slug = 'ohm' AND action_kind = 'graduate_complete'
+             ORDER BY id DESC LIMIT 1
+            """
+        ).fetchone()
+        assert complete is not None
+        assert _json.loads(complete["details"])["rfc_id"] is None
+
+
+def test_graduate_with_number_unchanged_when_id_absent_field(app_with_fake_gitea):
+    """Omitting the rfc_id field entirely is treated the same as blank —
+    graduates without a number — so older clients that drop the field don't
+    break, and the supplied-number path stays exactly as before."""
+    from fastapi.testclient import TestClient
+    from app import entry as entry_mod
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM", pitch=PITCH, owners=["ben"])
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner")
+
+        r = client.post("/api/rfcs/ohm/graduate?_sync=1", json={"owners": ["ben"]})
+        assert r.status_code == 200, r.text
+        assert r.json()["rfc_id"] is None
+        graduated = entry_mod.parse(
+            fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
+        )
+        assert graduated.state == "active"
+        assert graduated.id is None
 
 
 def test_claim_opens_meta_pr(app_with_fake_gitea):
@@ -554,12 +649,10 @@ def test_claim_opens_meta_pr(app_with_fake_gitea):
         d = r.json()
         assert d["branch_name"] == "claim/ohm"
 
-        # The PR body's diff carries Alice in owners.
         text = fake.files[("wiggleverse", "meta", "claim/ohm", "rfcs/ohm.md")]["content"]
         ent = entry_mod.parse(text)
         assert "alice" in ent.owners
 
-        # cached_prs records pr_kind='meta_claim' via refresh_meta_pulls.
         row = db.conn().execute(
             "SELECT pr_kind FROM cached_prs WHERE pr_number = ?", (d["pr_number"],),
         ).fetchone()

backend/tests/test_hygiene_vertical.py

@@ -339,10 +339,10 @@ def test_hygiene_action_kinds_fire_no_notifications(app_with_fake_gitea):
 
 
 def test_graduation_rollback_deletes_dash_suffixed_branch(app_with_fake_gitea):
-    """§19.2 candidate Slice 8 settles: when graduation rolls back
-    after step 3 (open_pr), the `graduate-<slug>-<6hex>` branch is
-    deleted alongside the PR close so failed-graduation branches
-    don't accumulate on the meta repo across retries."""
+    """Meta-only (§13.3): when the flip's merge fails after the PR is
+    open, the orchestrator closes the PR and deletes its
+    `graduate-<slug>-<6hex>` branch so failed attempts don't accumulate
+    on the meta repo across retries."""
     from fastapi.testclient import TestClient
     from app import db
     from app.bot import Bot
@@ -359,24 +359,23 @@ def test_graduation_rollback_deletes_dash_suffixed_branch(app_with_fake_gitea):
         sign_in_as(client, user_id=1, gitea_login="ben",
                    display_name="Ben", role="owner")
 
-        # Force a step-4 (merge_pr) failure so step 3 (open_pr) has
-        # already landed and the rollback exercises the branch cleanup.
+        # Force a merge_pr failure so the flip PR (open_pr) has already
+        # landed and the cleanup exercises the branch deletion.
         orig_merge = Bot.merge_graduation_pr
         async def boom(self, *args, **kwargs):
-            raise GiteaError(502, "simulated merge failure for rollback test")
+            raise GiteaError(502, "simulated merge failure for cleanup test")
         Bot.merge_graduation_pr = boom
         try:
             r = client.post(
                 "/api/rfcs/ohm/graduate?_sync=1",
-                json={"rfc_id": "RFC-0099", "repo_name": "rfc-0099-ohm",
-                      "owners": ["ben"]},
+                json={"rfc_id": "RFC-0099", "owners": ["ben"]},
             )
         finally:
             Bot.merge_graduation_pr = orig_merge
         assert r.status_code == 200, r.text
         assert r.json()["succeeded"] is False
 
-        # The dash-suffixed graduation branch was deleted on rollback.
+        # The dash-suffixed graduation branch was deleted on cleanup.
         meta_branches = fake.branches[("wiggleverse", "meta")]
         graduation_branches = [n for n in meta_branches if n.startswith("graduate-ohm-")]
         assert graduation_branches == [], (

backend/tests/test_initial_state_landing.py

@@ -0,0 +1,43 @@
+"""§22.4b — a project with initial_state='active' lands new entries active +
+unreviewed; the default 'super-draft' project is unchanged."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _propose(client):
+    return client.post("/api/rfcs/propose", json={
+        "title": "Active Lander", "slug": "active-lander",
+        "pitch": "Lands active.", "tags": [],
+    })
+
+
+def test_super_draft_default_unchanged(app_with_fake_gitea):
+    from app import entry as entry_mod
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner")
+        assert _propose(client).status_code == 200
+        f = fake.files[("wiggleverse", "meta", "propose/active-lander", "rfcs/active-lander.md")]
+        e = entry_mod.parse(f["content"])
+        assert e.state == "super-draft"
+        assert e.unreviewed is False
+
+
+def test_active_initial_state_lands_active_unreviewed(app_with_fake_gitea):
+    from app import db, entry as entry_mod
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        db.conn().execute("UPDATE collections SET initial_state='active' WHERE project_id='default'")
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner")
+        assert _propose(client).status_code == 200
+        f = fake.files[("wiggleverse", "meta", "propose/active-lander", "rfcs/active-lander.md")]
+        e = entry_mod.parse(f["content"])
+        assert e.state == "active"
+        assert e.unreviewed is True

backend/tests/test_mark_reviewed.py

@@ -0,0 +1,65 @@
+"""§22.4c — owner/admin mark-reviewed clears the flag; catalog unreviewed filter."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _seed_unreviewed_active(fake, slug="feat"):
+    """Put an active+unreviewed entry on the meta repo main + cache."""
+    from app import cache, entry as entry_mod
+    body = entry_mod.serialize(entry_mod.Entry(
+        slug=slug, title="Feat", state="active", unreviewed=True,
+        owners=["ben"], proposed_by="ben",
+    ))
+    fake.files[("wiggleverse", "meta", "main", f"rfcs/{slug}.md")] = {"content": body, "sha": "s1"}
+    cache._upsert_cached_rfc(entry_mod.parse(body), body_sha="s1")
+
+
+def test_catalog_unreviewed_filter(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_unreviewed_active(fake, "feat")
+        from app import cache, entry as entry_mod
+        ok = entry_mod.serialize(entry_mod.Entry(slug="ok", title="OK", state="active", owners=["ben"]))
+        fake.files[("wiggleverse", "meta", "main", "rfcs/ok.md")] = {"content": ok, "sha": "s2"}
+        cache._upsert_cached_rfc(entry_mod.parse(ok), body_sha="s2")
+        r = client.get("/api/rfcs", params={"unreviewed": "true"})
+        slugs = {i["slug"] for i in r.json()["items"]}
+        assert slugs == {"feat"}
+
+
+def test_mark_reviewed_clears_flag(app_with_fake_gitea):
+    from app import db
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_unreviewed_active(fake, "feat")
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner")
+        r = client.post("/api/projects/default/rfcs/feat/mark-reviewed")
+        assert r.status_code == 200
+        row = db.conn().execute(
+            "SELECT unreviewed, reviewed_at, reviewed_by FROM cached_rfcs WHERE slug='feat'"
+        ).fetchone()
+        assert row["unreviewed"] == 0
+        assert row["reviewed_by"] == "ben"
+        assert row["reviewed_at"]  # provenance stamped
+        # git-side: the entry file on main was rewritten with the cleared flag.
+        from app import entry as entry_mod
+        written = fake.files[("wiggleverse", "meta", "main", "rfcs/feat.md")]["content"]
+        e = entry_mod.parse(written)
+        assert e.unreviewed is False
+        assert e.reviewed_by == "ben"
+
+
+def test_mark_reviewed_forbidden_for_non_superuser(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _seed_unreviewed_active(fake, "feat")
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        sign_in_as(client, user_id=2, gitea_login="carol", display_name="Carol", role="contributor")
+        r = client.post("/api/projects/default/rfcs/feat/mark-reviewed")
+        assert r.status_code == 403

backend/tests/test_migration_027.py

@@ -0,0 +1,59 @@
+"""Migration 027 — additive §22 M3 schema (projects.type/initial_state, the
+deployment singleton, cached_rfcs review columns). No table rebuilds in Plan A."""
+from __future__ import annotations
+
+import tempfile
+from pathlib import Path
+
+from app import db
+from app.config import Config
+
+
+def _fresh_config() -> Config:
+    tmp = Path(tempfile.mkdtemp(prefix="mig027-")) / "t.db"
+    return Config(
+        gitea_url="x", gitea_bot_user="x", gitea_bot_token="x", gitea_org="x",
+        registry_repo="registry",
+        oauth_client_id="x", oauth_client_secret="x", app_url="x",
+        secret_key="x", database_path=tmp, owner_gitea_login="x",
+        webhook_secret="x",
+    )
+
+
+def test_027_adds_project_type_and_initial_state():
+    # 027 added type/initial_state to `projects`; migration 029 (three-tier)
+    # moved those per-corpus fields *down* onto `collections`. After the full
+    # migration chain they live on the collection, not the project.
+    cfg = _fresh_config()
+    db.run_migrations(cfg)
+    conn = db.connect(cfg.database_path)
+    proj_cols = {r["name"] for r in conn.execute("PRAGMA table_info(projects)")}
+    assert "type" not in proj_cols and "initial_state" not in proj_cols
+    coll_cols = {r["name"]: r for r in conn.execute("PRAGMA table_info(collections)")}
+    assert "type" in coll_cols and coll_cols["type"]["dflt_value"] == "'document'"
+    assert "initial_state" in coll_cols and coll_cols["initial_state"]["dflt_value"] == "'super-draft'"
+    conn.close()
+
+
+def test_027_creates_deployment_singleton():
+    cfg = _fresh_config()
+    db.run_migrations(cfg)
+    conn = db.connect(cfg.database_path)
+    rows = list(conn.execute("SELECT id FROM deployment"))
+    assert [r["id"] for r in rows] == [1]
+    try:
+        conn.execute("INSERT INTO deployment (id) VALUES (2)")
+        raised = False
+    except Exception:
+        raised = True
+    assert raised
+    conn.close()
+
+
+def test_027_adds_review_columns_to_cached_rfcs():
+    cfg = _fresh_config()
+    db.run_migrations(cfg)
+    conn = db.connect(cfg.database_path)
+    cols = {r["name"] for r in conn.execute("PRAGMA table_info(cached_rfcs)")}
+    assert {"unreviewed", "reviewed_at", "reviewed_by"} <= cols
+    conn.close()

backend/tests/test_migration_029_collections.py

@@ -0,0 +1,139 @@
+"""Migration 029 — the collection grain beneath projects (§22 three-tier S1).
+
+Proves: a `collections` table exists with one default collection per project
+(id='default', subfolder=repo root); the per-corpus fields (type, initial_state)
+moved off `projects`; the 13 entry-corpus tables re-key (project_id,slug) ->
+(collection_id,slug) with the composite PK/FK enforced; and project_members
+generalises into memberships(scope_type, …) with the role enum collapsed.
+Template: test_migration_028_project_scoped_keys.py.
+"""
+from __future__ import annotations
+
+import sqlite3
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from app import db
+
+
+class _Cfg:
+    def __init__(self, path):
+        self.database_path = path
+
+
+def _fresh_db():
+    d = tempfile.mkdtemp()
+    path = Path(d) / "t.db"
+    db.run_migrations(_Cfg(str(path)))
+    return db.connect(str(path))
+
+
+def test_collections_table_exists_with_default_per_project():
+    conn = _fresh_db()
+    cols = {r["name"] for r in conn.execute("PRAGMA table_info(collections)")}
+    assert {"id", "project_id", "type", "subfolder",
+            "initial_state", "visibility", "name", "registry_sha"} <= cols
+    # one default collection seeded for the bootstrap 'default' project (026)
+    row = conn.execute(
+        "SELECT id, project_id, subfolder FROM collections WHERE project_id='default'"
+    ).fetchone()
+    assert row is not None
+    assert row["id"] == "default"
+    assert row["subfolder"] == ""  # repo root
+
+
+def test_per_corpus_fields_moved_off_projects():
+    conn = _fresh_db()
+    proj_cols = {r["name"] for r in conn.execute("PRAGMA table_info(projects)")}
+    assert "type" not in proj_cols
+    assert "initial_state" not in proj_cols
+    # projects keeps the grouping-tier fields
+    assert {"id", "name", "content_repo", "visibility"} <= proj_cols
+
+
+def test_entry_tables_rekeyed_to_collection_id():
+    conn = _fresh_db()
+    for t in ("cached_rfcs", "cached_branches", "stars", "watches",
+              "rfc_collaborators", "contribution_requests", "proposed_use_cases",
+              "branch_visibility", "branch_contribute_grants", "pr_seen",
+              "branch_chat_seen", "funder_consents", "rfc_invitations"):
+        cols = {r["name"] for r in conn.execute(f"PRAGMA table_info({t})")}
+        assert "collection_id" in cols, f"{t} missing collection_id"
+        assert "project_id" not in cols, f"{t} still has project_id"
+
+
+def test_cached_rfcs_pk_is_collection_slug():
+    conn = _fresh_db()
+    # a second collection under the default project
+    conn.execute(
+        "INSERT INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES ('c2','default','document','specs','active','public','Specs')"
+    )
+    conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','A','active','default')")
+    conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','B','active','c2')")
+    n = conn.execute("SELECT COUNT(*) c FROM cached_rfcs WHERE slug='intro'").fetchone()["c"]
+    assert n == 2
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','dup','active','default')")
+
+
+def test_cached_rfcs_collection_fk_enforced():
+    conn = _fresh_db()
+    conn.execute("PRAGMA foreign_keys=ON")
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('x','X','active','nope')")
+
+
+def test_collaborator_fk_is_composite_on_collection():
+    conn = _fresh_db()
+    conn.execute(
+        "INSERT INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES ('c2','default','document','specs','active','public','Specs')"
+    )
+    conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','A','active','c2')")
+    conn.execute("INSERT INTO users (id, gitea_login, display_name, role) VALUES (1,'a','A','contributor')")
+    conn.execute("PRAGMA foreign_keys=ON")
+    conn.execute(
+        "INSERT INTO rfc_collaborators (rfc_slug, user_id, role_in_rfc, collection_id) "
+        "VALUES ('intro',1,'contributor','c2')"
+    )
+    with pytest.raises(sqlite3.IntegrityError):
+        # same slug, a collection with no such entry — composite FK rejects
+        conn.execute(
+            "INSERT INTO rfc_collaborators (rfc_slug, user_id, role_in_rfc, collection_id) "
+            "VALUES ('intro',1,'contributor','default')"
+        )
+
+
+def test_stars_unique_now_scoped_by_collection():
+    conn = _fresh_db()
+    conn.execute(
+        "INSERT INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES ('c2','default','document','specs','active','public','Specs')"
+    )
+    conn.execute("INSERT INTO users (id, gitea_login, display_name, role) VALUES (1,'a','A','contributor')")
+    conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','A','active','default')")
+    conn.execute("INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES ('intro','B','active','c2')")
+    conn.execute("INSERT INTO stars (user_id, rfc_slug, collection_id) VALUES (1,'intro','default')")
+    conn.execute("INSERT INTO stars (user_id, rfc_slug, collection_id) VALUES (1,'intro','c2')")
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute("INSERT INTO stars (user_id, rfc_slug, collection_id) VALUES (1,'intro','default')")
+
+
+def test_memberships_table_replaces_project_members():
+    conn = _fresh_db()
+    cols = {r["name"] for r in conn.execute("PRAGMA table_info(memberships)")}
+    assert {"scope_type", "scope_id", "user_id", "role", "granted_by", "granted_at"} <= cols
+    # project_members is gone
+    assert conn.execute(
+        "SELECT name FROM sqlite_master WHERE type='table' AND name='project_members'"
+    ).fetchone() is None
+    conn.execute("INSERT INTO users (id, gitea_login, display_name, role) VALUES (9,'x','X','contributor')")
+    conn.execute("INSERT INTO memberships (scope_type, scope_id, user_id, role) VALUES ('project','default',9,'owner')")
+    # scope_type and role are CHECK-constrained
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute("INSERT INTO memberships (scope_type, scope_id, user_id, role) VALUES ('bogus','default',9,'owner')")
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute("INSERT INTO memberships (scope_type, scope_id, user_id, role) VALUES ('project','default',9,'viewer')")

backend/tests/test_migration_030_global_scope.py

@@ -0,0 +1,91 @@
+"""Migration 030 — the global-scope grant (§22 three-tier S3).
+
+Proves: `memberships.scope_type` now admits 'global' alongside 'project' and
+'collection' (§B.2's four-layer resolver), existing rows survive the rebuild,
+and the UNIQUE(scope_type, scope_id, user_id) shape is preserved.
+Template: test_migration_029_collections.py.
+"""
+from __future__ import annotations
+
+import sqlite3
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from app import db
+
+
+class _Cfg:
+    def __init__(self, path):
+        self.database_path = path
+
+
+def _fresh_db():
+    d = tempfile.mkdtemp()
+    path = Path(d) / "t.db"
+    db.run_migrations(_Cfg(str(path)))
+    return db.connect(str(path))
+
+
+def _add_user(conn, uid, login):
+    conn.execute(
+        "INSERT INTO users (id, gitea_id, gitea_login, display_name, role) "
+        "VALUES (?, ?, ?, ?, 'contributor')",
+        (uid, uid, login, login.capitalize()),
+    )
+
+
+def test_global_scope_type_is_accepted():
+    conn = _fresh_db()
+    _add_user(conn, 1, "cleo")
+    # global grant — the new tier — is accepted.
+    conn.execute(
+        "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+        "VALUES ('global', '*', 1, 'contributor')"
+    )
+    row = conn.execute(
+        "SELECT scope_type, scope_id, role FROM memberships WHERE user_id = 1"
+    ).fetchone()
+    assert row["scope_type"] == "global"
+    assert row["scope_id"] == "*"
+    assert row["role"] == "contributor"
+
+
+def test_project_and_collection_scopes_still_accepted():
+    conn = _fresh_db()
+    _add_user(conn, 1, "ben")
+    conn.execute(
+        "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+        "VALUES ('project', 'default', 1, 'owner')"
+    )
+    conn.execute(
+        "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+        "VALUES ('collection', 'default', 1, 'contributor')"
+    )
+    n = conn.execute("SELECT COUNT(*) AS n FROM memberships WHERE user_id = 1").fetchone()["n"]
+    assert n == 2
+
+
+def test_unknown_scope_type_still_rejected():
+    conn = _fresh_db()
+    _add_user(conn, 1, "x")
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute(
+            "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+            "VALUES ('deployment', '*', 1, 'owner')"
+        )
+
+
+def test_one_global_grant_per_user():
+    conn = _fresh_db()
+    _add_user(conn, 1, "cleo")
+    conn.execute(
+        "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+        "VALUES ('global', '*', 1, 'contributor')"
+    )
+    with pytest.raises(sqlite3.IntegrityError):
+        conn.execute(
+            "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+            "VALUES ('global', '*', 1, 'owner')"
+        )

backend/tests/test_multi_project_authz_vertical.py

@@ -0,0 +1,358 @@
+"""Slice M2 — project-scoped authorization + the §22.7 resolver.
+
+M1 laid the schema spine (the `projects` / `project_members` tables and the
+`project_id` column on every slug-bearing table). M2 builds the resolver on top:
+the most-permissive union of the deployment role (§6.1), the project role
+(§22.6), and the per-RFC authority (§6.3/§12), with the §22.5 visibility gate
+subtractive on top (§22.7).
+
+Two operator decisions are pinned here as executable expectations:
+
+  * implicit-on-public — a granted deployment `contributor` keeps its
+    pre-multi-project write *baseline* on a `public` project (propose freely;
+    an owned RFC's discuss/contribute still needs the per-RFC invite) with no
+    project_members row. So the single public default project behaves exactly
+    as it did before M2 (verified across the rest of the suite, and the
+    `*_public_*` tests below).
+  * preserve curation — the implicit-public baseline does NOT override per-RFC
+    owner curation; only an *explicit* project_contributor/admin grant (or a
+    deployment owner/admin) bypasses it.
+
+Everything is exercised on the single `default` project by flipping its
+visibility and granting/revoking `project_members` roles — the M2 slice is
+verifiable without a second project (which arrives with M3's registry mirror).
+"""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401 — fixtures land via import
+    app_with_fake_gitea,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+
+
+# ---------------------------------------------------------------------------
+# Helpers
+# ---------------------------------------------------------------------------
+
+
+def _su(user_id: int, login: str, role: str, *, state: str = "granted"):
+    """A SessionUser handle for direct resolver calls (the endpoint tests use
+    sign_in_as instead)."""
+    from app import auth
+
+    return auth.SessionUser(
+        user_id=user_id,
+        gitea_id=user_id,
+        gitea_login=login,
+        display_name=login.capitalize(),
+        email=f"{login}@test",
+        avatar_url="",
+        role=role,
+        permission_state=state,
+    )
+
+
+def _set_visibility(project_id: str, visibility: str) -> None:
+    from app import db
+
+    db.conn().execute(
+        "UPDATE projects SET visibility = ? WHERE id = ?", (visibility, project_id)
+    )
+
+
+# §22 three-tier (§B.3): M2's three project roles collapse to {owner,
+# contributor} in the unified `memberships` table at the project's default
+# collection. The read-only `viewer` tier is deferred (folded into contributor
+# for this pass), so the legacy role names map: admin→owner, contributor and
+# viewer→contributor.
+_ROLE_MAP = {
+    "project_admin": "owner",
+    "project_contributor": "contributor",
+    "project_viewer": "contributor",
+}
+
+
+def _add_member(project_id: str, user_id: int, role: str) -> None:
+    from app import collections as collections_mod, db
+
+    cid = collections_mod.default_collection_id(project_id)
+    db.conn().execute(
+        "INSERT OR REPLACE INTO memberships (scope_type, scope_id, user_id, role) "
+        "VALUES ('collection', ?, ?, ?)",
+        (cid, user_id, _ROLE_MAP[role]),
+    )
+
+
+def _remove_member(project_id: str, user_id: int) -> None:
+    from app import collections as collections_mod, db
+
+    cid = collections_mod.default_collection_id(project_id)
+    db.conn().execute(
+        "DELETE FROM memberships WHERE scope_type = 'collection' AND scope_id = ? AND user_id = ?",
+        (cid, user_id),
+    )
+
+
+def _seed_rfc(slug: str, *, state: str = "active", owners=None, project_id: str = "default") -> None:
+    """A minimal cached_rfcs row — enough for the authz gates (state, owners,
+    collection grain). The entry lands in the project's default collection
+    (id == project_id for the single 'default' project under test)."""
+    import json
+
+    from app import collections as collections_mod, db
+
+    cid = collections_mod.default_collection_id(project_id)
+    db.conn().execute(
+        """
+        INSERT OR REPLACE INTO cached_rfcs
+            (slug, title, state, owners_json, arbiters_json, tags_json, collection_id)
+        VALUES (?, ?, ?, ?, '[]', '[]', ?)
+        """,
+        (slug, slug.capitalize(), state, json.dumps(owners or []), cid),
+    )
+
+
+# ---------------------------------------------------------------------------
+# 1. The §22.7 resolver — tier composition
+# ---------------------------------------------------------------------------
+
+
+def test_resolver_public_project_tiers(app_with_fake_gitea):
+    from app import auth
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        provision_user_row(user_id=1, login="alice", role="contributor")
+        provision_user_row(user_id=2, login="ben", role="owner")
+        contributor = _su(1, "alice", "contributor")
+        owner = _su(2, "ben", "owner")
+
+        # default is public — read open to everyone incl. anonymous.
+        assert auth.can_read_project(None, "default") is True
+        assert auth.can_read_project(contributor, "default") is True
+
+        # implicit-on-public: a granted deployment contributor carries the
+        # write baseline without a project_members row.
+        assert auth.can_contribute_in_project(contributor, "default") is True
+        assert auth.can_discuss_in_project(contributor, "default") is True
+
+        # ... but it is NOT project_admin (curation/override authority).
+        assert auth.is_project_superuser(contributor, "default") is False
+        # a deployment owner/admin is a superuser in every project.
+        assert auth.is_project_superuser(owner, "default") is True
+
+        # a pending contributor has no write standing (the §6 admission floor).
+        pending = _su(1, "alice", "contributor", state="pending")
+        assert auth.can_contribute_in_project(pending, "default") is False
+
+
+def test_resolver_gated_project_requires_membership(app_with_fake_gitea):
+    from app import auth
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        provision_user_row(user_id=1, login="alice", role="contributor")
+        provision_user_row(user_id=2, login="ben", role="owner")
+        _set_visibility("default", "gated")
+        contributor = _su(1, "alice", "contributor")
+        owner = _su(2, "ben", "owner")
+
+        # gated: no membership → invisible and no standing.
+        assert auth.can_read_project(None, "default") is False
+        assert auth.can_read_project(contributor, "default") is False
+        assert auth.can_contribute_in_project(contributor, "default") is False
+
+        # deployment owner is a superuser regardless of membership.
+        assert auth.can_read_project(owner, "default") is True
+        assert auth.is_project_superuser(owner, "default") is True
+
+        # §22 three-tier (§B.3): the read-only viewer tier is deferred — the
+        # smallest grant is `contributor`, which grants read + discuss +
+        # contribute across the subtree.
+        _add_member("default", 1, "project_contributor")
+        assert auth.can_read_project(contributor, "default") is True
+        assert auth.can_discuss_in_project(contributor, "default") is True
+        assert auth.can_contribute_in_project(contributor, "default") is True
+        assert auth.is_project_superuser(contributor, "default") is False
+
+        # project_admin → owner → superuser within the project.
+        _add_member("default", 1, "project_admin")
+        assert auth.is_project_superuser(contributor, "default") is True
+
+
+# ---------------------------------------------------------------------------
+# 2. Public default unchanged — the regression floor (curation preserved)
+# ---------------------------------------------------------------------------
+
+
+def test_public_per_rfc_curation_preserved(app_with_fake_gitea):
+    """On the public default project a granted contributor still cannot
+    discuss an *owned* RFC without a per-RFC invite (the v0.16.0 contract);
+    but an unclaimed (no-owners) entry stays open. This is the implicit-public
+    baseline with curation preserved."""
+    from app import auth
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        provision_user_row(user_id=1, login="alice", role="contributor")
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        bob = _su(2, "bob", "contributor")
+
+        _seed_rfc("owned", state="active", owners=["alice"])
+        assert auth.can_discuss_rfc(bob, "owned") is False
+        assert auth.can_contribute_to_rfc(bob, "owned") is False
+
+        _seed_rfc("draft", state="super-draft", owners=[])
+        assert auth.can_discuss_rfc(bob, "draft") is True
+        assert auth.can_contribute_to_rfc(bob, "draft") is True
+
+
+def test_public_read_open_write_gated_endpoints(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        _seed_rfc("ohm", state="active", owners=["alice"])
+
+        # anonymous can read the entry on a public project.
+        r = client.get("/api/rfcs/ohm")
+        assert r.status_code == 200, r.text
+
+        # anonymous cannot open a discussion thread (401, the §6 write floor).
+        r = client.post("/api/rfcs/ohm/discussion/threads", json={"message": "hi"})
+        assert r.status_code == 401
+
+
+# ---------------------------------------------------------------------------
+# 3. The §22.5 visibility gate — 404 to non-members on read
+# ---------------------------------------------------------------------------
+
+
+def test_gated_project_404s_non_members(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="alice", role="contributor")
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        provision_user_row(user_id=3, login="ben", role="owner")
+        _seed_rfc("sekret", state="active", owners=["alice"])
+        _set_visibility("default", "gated")
+
+        # anonymous → 404 (indistinguishable from an unknown slug).
+        assert client.get("/api/rfcs/sekret").status_code == 404
+
+        # signed-in non-member → 404 on the entry and its discussion.
+        sign_in_as(client, user_id=2, gitea_login="bob", display_name="Bob", role="contributor")
+        assert client.get("/api/rfcs/sekret").status_code == 404
+        assert client.get("/api/rfcs/sekret/discussion/threads").status_code == 404
+        # the gated entry never surfaces in the non-member's catalog.
+        assert client.get("/api/rfcs").json()["items"] == []
+
+        # a project_viewer member can read again.
+        _add_member("default", 2, "project_viewer")
+        assert client.get("/api/rfcs/sekret").status_code == 200
+        assert [i["slug"] for i in client.get("/api/rfcs").json()["items"]] == ["sekret"]
+
+        # a deployment owner can always read.
+        sign_in_as(client, user_id=3, gitea_login="ben", display_name="Ben", role="owner")
+        assert client.get("/api/rfcs/sekret").status_code == 200
+
+
+# ---------------------------------------------------------------------------
+# 4. The contribution gate on a gated project (401/403)
+# ---------------------------------------------------------------------------
+
+
+def test_gated_propose_requires_project_contributor(app_with_fake_gitea):
+    """Propose checks project-level contribute standing before any Gitea
+    work, so the gate is observable as a 403 (gated, non-member) without
+    seeding the success path."""
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        _set_visibility("default", "gated")
+        sign_in_as(client, user_id=2, gitea_login="bob", display_name="Bob", role="contributor")
+
+        body = {"slug": "newidea", "title": "New Idea", "pitch": "A pitch.", "tags": []}
+        assert client.post("/api/rfcs/propose", json=body).status_code == 403
+
+        # grant project_contributor — the project gate now passes (the request
+        # proceeds past the gate; we assert only that it is no longer 403).
+        _add_member("default", 2, "project_contributor")
+        assert client.post("/api/rfcs/propose", json=body).status_code != 403
+
+
+def test_gated_member_can_discuss_and_contribute(app_with_fake_gitea):
+    from app import auth
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        _seed_rfc("spec", state="super-draft", owners=[])
+        _set_visibility("default", "gated")
+        bob = _su(2, "bob", "contributor")
+
+        # non-member: discussion thread create → 404 (visibility, before the
+        # write gate even applies).
+        sign_in_as(client, user_id=2, gitea_login="bob", display_name="Bob", role="contributor")
+        assert client.post("/api/rfcs/spec/discussion/threads", json={"message": "q"}).status_code == 404
+
+        # §22 three-tier (§B.3): a `contributor` member can both discuss and
+        # contribute (the viewer-only read tier is deferred this pass).
+        _add_member("default", 2, "project_contributor")
+        r = client.post("/api/rfcs/spec/discussion/threads", json={"message": "q"})
+        assert r.status_code == 200, r.text
+        assert auth.can_contribute_to_rfc(bob, "spec") is True
+
+
+# ---------------------------------------------------------------------------
+# 5. Union of tiers + subtractive visibility gate
+# ---------------------------------------------------------------------------
+
+
+def test_per_rfc_authority_unions_then_yields_to_visibility(app_with_fake_gitea):
+    from app import auth
+    from test_propose_vertical import grant_rfc_collaborator
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        _seed_rfc("owned", state="active", owners=["alice"])
+        bob = _su(2, "bob", "contributor")
+
+        # public + per-RFC collaborator(contributor) → contribute (union term).
+        grant_rfc_collaborator(user_id=2, rfc_slug="owned", role_in_rfc="contributor")
+        assert auth.can_contribute_to_rfc(bob, "owned") is True
+
+        # flip to gated: the §22.5 gate is subtractive — the per-RFC grant no
+        # longer suffices without project membership.
+        _set_visibility("default", "gated")
+        assert auth.can_contribute_to_rfc(bob, "owned") is False
+
+        # restore read via project membership → the per-RFC union applies again.
+        _add_member("default", 2, "project_viewer")
+        assert auth.can_contribute_to_rfc(bob, "owned") is True
+
+
+# ---------------------------------------------------------------------------
+# 6. Revocation takes effect on the next call
+# ---------------------------------------------------------------------------
+
+
+def test_revoking_membership_revokes_access(app_with_fake_gitea):
+    from app import auth
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        provision_user_row(user_id=2, login="bob", role="contributor")
+        _set_visibility("default", "gated")
+        bob = _su(2, "bob", "contributor")
+
+        _add_member("default", 2, "project_contributor")
+        assert auth.can_contribute_in_project(bob, "default") is True
+
+        _remove_member("default", 2)
+        assert auth.can_read_project(bob, "default") is False
+        assert auth.can_contribute_in_project(bob, "default") is False

backend/tests/test_multi_project_spine_vertical.py

@@ -0,0 +1,147 @@
+"""Slice M1+M3 — the §22 multi-project spine.
+
+Migration 026 introduces the `projects` and `project_members` tables, seeds
+the single `default` project (the N=1 case, §22.13), and threads a
+`project_id` column onto every slug-bearing table, backfilled to `default`.
+M3 retires the META_REPO startup backfill; content_repo now comes from the
+registry mirror (projects.yaml in REGISTRY_REPO). These tests prove the
+spine lands without disturbing the single-project app.
+"""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea,
+    tmp_env,
+)
+
+# §22 three-tier (migration 029): the entry-corpus grain is the collection, so
+# the 13 tables migration 028 keyed by project_id re-key to collection_id. The
+# remaining tables 026 tagged keep their denormalised project_id (project grain).
+COLLECTION_TABLES = [
+    "cached_rfcs", "cached_branches", "branch_visibility",
+    "branch_contribute_grants", "stars", "pr_seen", "branch_chat_seen",
+    "watches", "funder_consents", "rfc_invitations", "rfc_collaborators",
+    "proposed_use_cases", "contribution_requests",
+]
+PROJECT_TAG_TABLES = [
+    "cached_prs", "threads", "changes", "notifications", "actions",
+    "pr_resolution_branches",
+]
+
+
+def test_default_project_seeded_and_backfilled(app_with_fake_gitea):
+    from app import db
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        rows = list(db.conn().execute(
+            "SELECT id, name, visibility, content_repo FROM projects"
+        ))
+        assert len(rows) == 1
+        row = rows[0]
+        assert row["id"] == "default"
+        # public preserves the pre-multi-project open-by-default posture.
+        assert row["visibility"] == "public"
+        # M3: content_repo now comes from the registry mirror (projects.yaml),
+        # not the retired META_REPO startup backfill.
+        assert row["content_repo"] == "meta"
+
+
+def test_grain_columns_on_every_slug_table(app_with_fake_gitea):
+    from app import db
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        # The entry-corpus tables key on collection_id (NOT NULL, 'default').
+        for table in COLLECTION_TABLES:
+            cols = {r["name"]: r for r in db.conn().execute(f"PRAGMA table_info({table})")}
+            assert "collection_id" in cols, f"{table} missing collection_id"
+            assert "project_id" not in cols, f"{table} should no longer have project_id"
+            col = cols["collection_id"]
+            assert col["notnull"] == 1, f"{table}.collection_id should be NOT NULL"
+            assert col["dflt_value"] == "'default'", f"{table}.collection_id default"
+        # The project-tag tables keep their denormalised project_id.
+        for table in PROJECT_TAG_TABLES:
+            cols = {r["name"] for r in db.conn().execute(f"PRAGMA table_info({table})")}
+            assert "project_id" in cols, f"{table} missing project_id tag"
+
+
+def test_existing_row_backfills_to_default(app_with_fake_gitea):
+    """A row inserted the old way (no collection grain) lands in the default
+    collection — the trick that keeps every pre-three-tier INSERT working."""
+    from app import db
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        db.conn().execute(
+            "INSERT INTO cached_rfcs (slug, title, state) VALUES (?, ?, ?)",
+            ("human", "Human", "active"),
+        )
+        got = db.conn().execute(
+            "SELECT collection_id FROM cached_rfcs WHERE slug = 'human'"
+        ).fetchone()["collection_id"]
+        assert got == "default"
+
+
+def test_memberships_table_shape(app_with_fake_gitea):
+    from app import db
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        # §22 three-tier: project_members generalised into memberships.
+        assert db.conn().execute(
+            "SELECT name FROM sqlite_master WHERE type='table' AND name='project_members'"
+        ).fetchone() is None
+        cols = {r["name"] for r in db.conn().execute("PRAGMA table_info(memberships)")}
+        assert {"scope_type", "scope_id", "user_id", "role", "granted_by", "granted_at"} <= cols
+        db.conn().execute(
+            "INSERT INTO users (id, display_name, role) VALUES (1, 'Ben', 'owner')"
+        )
+        db.conn().execute(
+            "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+            "VALUES ('collection', 'default', 1, 'owner')"
+        )
+        import sqlite3
+        try:
+            db.conn().execute(
+                "INSERT INTO memberships (scope_type, scope_id, user_id, role) "
+                "VALUES ('collection', 'default', 1, 'nonsense')"
+            )
+            assert False, "CHECK should reject an unknown role"
+        except sqlite3.IntegrityError:
+            pass
+
+
+def test_registry_mirror_is_idempotent(app_with_fake_gitea):
+    """Re-running the registry mirror is safe — it upserts (overwrites) the
+    projects row from projects.yaml each time without raising. M3 retirement
+    of seed_default_project: the registry mirror is now the sole authority."""
+    import asyncio
+    from app import db, registry as registry_mod
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        before = db.conn().execute("SELECT COUNT(*) AS n FROM projects").fetchone()["n"]
+        cfg = app.state.config
+        gitea = app.state.gitea
+        asyncio.run(registry_mod.refresh_registry(cfg, gitea))
+        after = db.conn().execute("SELECT COUNT(*) AS n FROM projects").fetchone()["n"]
+        assert after == before
+        row = db.conn().execute(
+            "SELECT content_repo FROM projects WHERE id='default'"
+        ).fetchone()
+        assert row["content_repo"] == "meta"
+
+
+def test_registry_repo_config_wired(app_with_fake_gitea, monkeypatch):
+    from app.config import load_config
+
+    monkeypatch.setenv("REGISTRY_REPO", "wiggleverse-registry")
+    assert load_config().registry_repo == "wiggleverse-registry"
+    # M3: REGISTRY_REPO is now required — absent raises RuntimeError.
+    monkeypatch.delenv("REGISTRY_REPO", raising=False)
+    import pytest
+    with pytest.raises(RuntimeError, match="REGISTRY_REPO"):
+        load_config()

backend/tests/test_notifications_vertical.py

@@ -612,3 +612,127 @@ def test_explicit_watch_set_overrides_auto(app_with_fake_gitea):
         # the user put them.
         assert row["set_by"] == "explicit"
         assert row["state"] == "following"
+
+
+# ---------------------------------------------------------------------------
+# v0.18.0 — envelope headers + RFC 8058 one-click POST endpoint
+#
+# Watcher notifications are bulk-adjacent (a busy RFC can produce
+# dozens of structural events); per the proposal, they MUST carry
+# `Date`, `Message-ID`, `Auto-Submitted`, full `List-Unsubscribe`
+# (mailto + signed URL), AND `List-Unsubscribe-Post:
+# List-Unsubscribe=One-Click` per RFC 8058. Gmail and Yahoo
+# enforce this for senders at OHM's volume tier.
+# ---------------------------------------------------------------------------
+
+
+def test_notification_envelope_carries_full_one_click_headers(app_with_fake_gitea):
+    """A `proposal_merged` event lands a watcher notification email
+    with the full one-click unsubscribe shape."""
+    from fastapi.testclient import TestClient
+    from email.utils import parsedate_to_datetime
+    from app import db, email as email_mod
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        provision_user_row(user_id=1, login="ben", role="owner")
+
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor", email="alice@test")
+        r = client.post("/api/rfcs/propose", json={"title": "OHM", "slug": "ohm", "pitch": PITCH, "tags": []})
+        assert r.status_code == 200
+        email_mod.reset_sent_envelopes()
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner", email="ben@test")
+        merge_r = client.post(f"/api/proposals/{r.json()['pr_number']}/merge")
+        assert merge_r.status_code == 200, merge_r.text
+
+        envelopes = [e for e in email_mod.sent_envelopes() if e["to"] == "alice@test"]
+        assert envelopes, "watcher notification did not fire"
+        msg = envelopes[-1]["message"]
+        # Always-present headers from the helper.
+        assert parsedate_to_datetime(msg["Date"]) is not None
+        assert msg["Message-ID"].startswith("<") and msg["Message-ID"].endswith(">")
+        assert msg["Auto-Submitted"] == "auto-generated"
+        # Full one-click unsubscribe.
+        lu = msg["List-Unsubscribe"]
+        assert lu is not None
+        assert "<mailto:" in lu
+        # URL part carries the signed token per make_unsubscribe_url.
+        assert "/api/email/unsubscribe?t=" in lu
+        assert msg["List-Unsubscribe-Post"] == "List-Unsubscribe=One-Click"
+
+
+def test_email_unsubscribe_post_one_click_flips_category_off(app_with_fake_gitea):
+    """RFC 8058: Gmail/Yahoo POST `List-Unsubscribe=One-Click` to the
+    URL in the List-Unsubscribe header. The endpoint MUST accept POST
+    + the same token shape as the GET handler + return 200 + flip the
+    flag."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        token = email_mod.make_unsubscribe_url(2, "personal-direct").split("t=", 1)[1]
+
+        r = client.post(
+            f"/api/email/unsubscribe?t={token}",
+            data={"List-Unsubscribe": "One-Click"},
+        )
+        assert r.status_code == 200, r.text
+        body = r.json()
+        assert body["ok"] is True
+        assert body["category"] == "personal-direct"
+
+        row = db.conn().execute(
+            "SELECT email_personal_direct FROM users WHERE id = 2"
+        ).fetchone()
+        assert row["email_personal_direct"] == 0
+
+
+def test_email_unsubscribe_post_all_sets_global_opt_out(app_with_fake_gitea):
+    """The v0.18.0 `all` synthetic category (used by the bundle +
+    digest paths) MUST set `email_opt_out_all = 1`."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        token = email_mod.make_unsubscribe_url(2, "all").split("t=", 1)[1]
+        r = client.post(f"/api/email/unsubscribe?t={token}")
+        assert r.status_code == 200
+        assert r.json() == {"ok": True, "category": "all"}
+        row = db.conn().execute(
+            "SELECT email_opt_out_all FROM users WHERE id = 2"
+        ).fetchone()
+        assert row["email_opt_out_all"] == 1
+
+
+def test_email_unsubscribe_get_all_sets_global_opt_out(app_with_fake_gitea):
+    """GET handler also accepts the `all` category and lands the
+    global opt-out (so an MUA that doesn't honor RFC 8058 POST and
+    just opens the URL in a browser still works)."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        token = email_mod.make_unsubscribe_url(2, "all").split("t=", 1)[1]
+        r = client.get(f"/api/email/unsubscribe?t={token}")
+        assert r.status_code == 200
+        assert "Unsubscribed" in r.text
+        row = db.conn().execute(
+            "SELECT email_opt_out_all FROM users WHERE id = 2"
+        ).fetchone()
+        assert row["email_opt_out_all"] == 1
+
+
+def test_email_unsubscribe_post_refuses_invalid_token(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.post("/api/email/unsubscribe?t=not-a-valid-token")
+        assert r.status_code == 400

backend/tests/test_otc_vertical.py

@@ -347,3 +347,53 @@ def test_otc_re_request_invalidates_prior_unused_code(app_with_fake_gitea, monke
         # The new code still works.
         r = client.post("/auth/otc/verify", json={"email": "alice@example.com", "code": second})
         assert r.status_code == 200
+
+
+# ---------------------------------------------------------------------------
+# v0.18.0: envelope headers — Slice 2
+#
+# OTC mail goes through `build_envelope` and MUST land Date,
+# Message-ID, and Auto-Submitted but MUST NOT carry a
+# List-Unsubscribe header (the recipient explicitly requested the
+# code; advertising a list semantic would be wrong).
+# ---------------------------------------------------------------------------
+
+
+def _last_otc_envelope():
+    from app import email as email_mod
+    otc = [e for e in email_mod.sent_envelopes() if e.get("kind") == "otc"]
+    assert otc, "no OTC envelope in the buffer"
+    return otc[-1]
+
+
+def test_otc_envelope_sets_date_messageid_autosubmitted(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from email.utils import parsedate_to_datetime
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _reset_outbound()
+        client.post("/auth/otc/request", json={"email": "headers@example.com"})
+        msg = _last_otc_envelope()["message"]
+        # Date is RFC 5322 parseable.
+        assert parsedate_to_datetime(msg["Date"]) is not None
+        # Message-ID is bracketed and carries the From-address @-domain.
+        mid = msg["Message-ID"]
+        assert mid.startswith("<") and mid.endswith(">")
+        # Auto-Submitted prevents auto-responder loops.
+        assert msg["Auto-Submitted"] == "auto-generated"
+
+
+def test_otc_envelope_has_no_list_unsubscribe(app_with_fake_gitea):
+    """The recipient explicitly typed their email and asked for a
+    code; the framework MUST NOT advertise a list semantic on this
+    mail. Per the v0.18.0 proposal's tradeoff discussion."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _reset_outbound()
+        client.post("/auth/otc/request", json={"email": "headers@example.com"})
+        msg = _last_otc_envelope()["message"]
+        assert msg["List-Unsubscribe"] is None
+        assert msg["List-Unsubscribe-Post"] is None

backend/tests/test_outbound_emails_vertical.py

@@ -0,0 +1,368 @@
+"""End-to-end integration tests for the v0.18.0 Slice 4
+outbound_emails audit table + admin endpoint.
+
+The release adds:
+  * `backend/migrations/020_outbound_emails.sql` — the audit table.
+  * `record_outbound()` in `email.py` — the write helper every send
+    path calls before returning, capturing status='sent' / 'failed'
+    / 'deferred' (the dev-fallback path when SMTP_HOST is unset).
+  * `GET /api/admin/outbound-emails` — admin-only listing, filterable
+    by kind / status / to_address.
+
+These tests prove:
+  * Sending OTC / invite / notification mail writes one row per send
+    (status='deferred' under tests since SMTP_HOST is unset).
+  * The Message-ID on the row matches the envelope's Message-ID
+    header (the seam Slice 5 uses for bounce correlation).
+  * `kind` is populated per send path.
+  * `GET /api/admin/outbound-emails` lists rows newest-first,
+    accepts filters, refuses non-admins.
+"""
+from __future__ import annotations
+
+from test_propose_vertical import (  # noqa: F401
+    FakeGitea,
+    app_with_fake_gitea,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+
+
+# ---------------------------------------------------------------------------
+# Write-on-send wiring
+# ---------------------------------------------------------------------------
+
+
+def test_otc_send_writes_outbound_row_with_message_id(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        email_mod.reset_sent_envelopes()
+        r = client.post("/auth/otc/request", json={"email": "newcomer@ex.co"})
+        assert r.status_code == 200
+
+        # Audit row landed.
+        rows = db.conn().execute(
+            "SELECT id, to_address, kind, status, message_id, error "
+            "FROM outbound_emails WHERE to_address = 'newcomer@ex.co'"
+        ).fetchall()
+        assert len(rows) == 1
+        row = rows[0]
+        assert row["kind"] == "otc"
+        # No SMTP_HOST in tests -> 'deferred', not 'sent'.
+        assert row["status"] == "deferred"
+        assert row["error"] is None
+        # Message-ID matches the envelope's header (the seam Slice 5 uses).
+        envelopes = [e for e in email_mod.sent_envelopes() if e.get("kind") == "otc"]
+        assert envelopes
+        envelope_mid = envelopes[-1]["message"]["Message-ID"]
+        assert row["message_id"] == envelope_mid
+
+
+def test_invite_send_writes_outbound_row(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=500, login="adminQ", role="admin")
+        sign_in_as(
+            client, user_id=500, gitea_login="adminQ",
+            display_name="Admin Q", role="admin",
+            email="adminq@test",
+        )
+        r = client.post(
+            "/api/admin/users",
+            json={
+                "email": "invitee@ex.co",
+                "first_name": "Inv", "last_name": "Itee",
+                "role": "contributor", "custom_message": "",
+            },
+        )
+        assert r.status_code == 200, r.text
+
+        rows = db.conn().execute(
+            "SELECT kind, status, message_id FROM outbound_emails "
+            "WHERE to_address = 'invitee@ex.co'"
+        ).fetchall()
+        assert len(rows) == 1
+        assert rows[0]["kind"] == "invite"
+        assert rows[0]["status"] == "deferred"
+        assert rows[0]["message_id"] is not None
+
+
+def test_notification_send_writes_outbound_row_with_notification_id(app_with_fake_gitea):
+    """Watcher notifications carry a `notification_id` FK so the
+    admin can join through to the notifications table to see what
+    triggered the send."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+    from test_notifications_vertical import PITCH
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(
+            client, user_id=2, gitea_login="alice",
+            display_name="Alice", role="contributor", email="alice@test",
+        )
+        r = client.post("/api/rfcs/propose", json={
+            "title": "OHM", "slug": "ohm", "pitch": PITCH, "tags": [],
+        })
+        email_mod.reset_sent_envelopes()
+        # Wipe pre-merge audit rows so the assertion below is unambiguous.
+        db.conn().execute("DELETE FROM outbound_emails")
+        sign_in_as(
+            client, user_id=1, gitea_login="ben",
+            display_name="Ben", role="owner", email="ben@test",
+        )
+        merge_r = client.post(f"/api/proposals/{r.json()['pr_number']}/merge")
+        assert merge_r.status_code == 200, merge_r.text
+
+        rows = db.conn().execute(
+            "SELECT kind, status, notification_id, message_id "
+            "FROM outbound_emails WHERE to_address = 'alice@test'"
+        ).fetchall()
+        assert rows, "no outbound_emails row for alice@test"
+        # At least one notification kind, with a populated FK.
+        notif_rows = [r for r in rows if r["kind"] == "notification"]
+        assert notif_rows
+        for nr in notif_rows:
+            assert nr["status"] == "deferred"
+            assert nr["notification_id"] is not None
+            assert nr["message_id"] is not None
+
+
+# ---------------------------------------------------------------------------
+# Admin endpoint
+# ---------------------------------------------------------------------------
+
+
+def test_admin_outbound_emails_lists_rows(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        # Generate a few rows.
+        client.post("/auth/otc/request", json={"email": "one@ex.co"})
+
+        provision_user_row(user_id=600, login="adminR", role="admin")
+        sign_in_as(
+            client, user_id=600, gitea_login="adminR",
+            display_name="Admin R", role="admin", email="adminr@test",
+        )
+        client.post("/api/admin/users", json={
+            "email": "two@ex.co", "first_name": "T", "last_name": "Wo",
+            "role": "contributor", "custom_message": "",
+        })
+
+        r = client.get("/api/admin/outbound-emails")
+        assert r.status_code == 200, r.text
+        items = r.json()["items"]
+        kinds = {it["kind"] for it in items}
+        assert "otc" in kinds
+        assert "invite" in kinds
+        # Newest-first.
+        ids = [it["id"] for it in items]
+        assert ids == sorted(ids, reverse=True)
+
+
+def test_admin_outbound_emails_filters_by_kind(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        client.post("/auth/otc/request", json={"email": "filter1@ex.co"})
+
+        provision_user_row(user_id=601, login="adminS", role="admin")
+        sign_in_as(
+            client, user_id=601, gitea_login="adminS",
+            display_name="Admin S", role="admin", email="admins@test",
+        )
+        client.post("/api/admin/users", json={
+            "email": "filter2@ex.co", "first_name": "F", "last_name": "Two",
+            "role": "contributor", "custom_message": "",
+        })
+
+        r = client.get("/api/admin/outbound-emails?kind=otc")
+        assert r.status_code == 200
+        items = r.json()["items"]
+        assert items
+        assert all(it["kind"] == "otc" for it in items)
+
+
+def test_admin_outbound_emails_filters_by_to_address(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        client.post("/auth/otc/request", json={"email": "TARGET@ex.co"})
+        client.post("/auth/otc/request", json={"email": "other@ex.co"})
+
+        provision_user_row(user_id=602, login="adminT", role="admin")
+        sign_in_as(
+            client, user_id=602, gitea_login="adminT",
+            display_name="Admin T", role="admin", email="admint@test",
+        )
+
+        # to_address filter is case-insensitive.
+        r = client.get("/api/admin/outbound-emails?to_address=target@ex.co")
+        assert r.status_code == 200
+        items = r.json()["items"]
+        assert items
+        assert all(it["to_address"].lower() == "target@ex.co" for it in items)
+
+
+def test_admin_outbound_emails_refuses_non_admin(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=700, login="contribU", role="contributor")
+        sign_in_as(
+            client, user_id=700, gitea_login="contribU",
+            display_name="Contrib U", role="contributor",
+        )
+        r = client.get("/api/admin/outbound-emails")
+        assert r.status_code == 403
+
+
+# ---------------------------------------------------------------------------
+# v0.18.0 Slice 5: bounce correlation
+# ---------------------------------------------------------------------------
+
+
+def test_bounce_with_message_id_marks_outbound_row_bounced(app_with_fake_gitea):
+    """When the bounce body includes the original `message_id`, the
+    framework looks it up in outbound_emails and stamps
+    status='bounced' on the matching row. The hard-bounce ->
+    global-opt-out logic still fires."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=800, login="bouncey", role="contributor")
+        db.conn().execute("UPDATE users SET email = 'bouncey@ex.co' WHERE id = 800")
+
+        # Send something to bouncey to land an outbound_emails row.
+        email_mod.reset_sent_envelopes()
+        client.post("/auth/otc/request", json={"email": "bouncey@ex.co"})
+        row = db.conn().execute(
+            "SELECT id, message_id, status FROM outbound_emails "
+            "WHERE to_address = 'bouncey@ex.co'"
+        ).fetchone()
+        assert row is not None
+        original_id = row["id"]
+        message_id = row["message_id"]
+        assert row["status"] == "deferred"  # pre-bounce baseline
+
+        # Bounce comes in carrying that message_id.
+        r = client.post(
+            "/api/webhooks/email-bounce",
+            json={
+                "email": "bouncey@ex.co",
+                "kind": "hard",
+                "message_id": message_id,
+            },
+        )
+        assert r.status_code == 200
+        body = r.json()
+        assert body["matched"] is True
+        assert body["correlated_id"] == original_id
+
+        # Audit row stamped.
+        post = db.conn().execute(
+            "SELECT status, error FROM outbound_emails WHERE id = ?",
+            (original_id,),
+        ).fetchone()
+        assert post["status"] == "bounced"
+        assert "bounce (hard)" in (post["error"] or "")
+
+        # Hard-bounce global opt-out still fires.
+        urow = db.conn().execute(
+            "SELECT email_opt_out_all FROM users WHERE id = 800"
+        ).fetchone()
+        assert urow["email_opt_out_all"] == 1
+
+
+def test_bounce_with_unknown_message_id_does_not_crash(app_with_fake_gitea):
+    """A message_id the framework doesn't recognize logs but does
+    NOT 5xx — bounce providers replay old bounces, and the
+    framework can't refuse just because the row was pruned."""
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        r = client.post(
+            "/api/webhooks/email-bounce",
+            json={
+                "email": "nobody@ex.co",
+                "kind": "hard",
+                "message_id": "<not-in-our-db@ex.co>",
+            },
+        )
+        assert r.status_code == 200
+        assert r.json()["correlated_id"] is None
+
+
+def test_bounce_without_message_id_still_flips_opt_out(app_with_fake_gitea):
+    """Backward compat: providers that don't surface Message-ID
+    still get the legacy v1 behavior — match by email + flip the
+    global opt-out."""
+    from fastapi.testclient import TestClient
+    from app import db
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=801, login="legacybounce", role="contributor")
+        db.conn().execute("UPDATE users SET email = 'legacy@ex.co' WHERE id = 801")
+
+        r = client.post(
+            "/api/webhooks/email-bounce",
+            json={"email": "legacy@ex.co", "kind": "hard"},
+        )
+        assert r.status_code == 200
+        body = r.json()
+        assert body["matched"] is True
+        assert body["correlated_id"] is None
+
+        urow = db.conn().execute(
+            "SELECT email_opt_out_all FROM users WHERE id = 801"
+        ).fetchone()
+        assert urow["email_opt_out_all"] == 1
+
+
+def test_bounced_rows_show_in_admin_endpoint(app_with_fake_gitea):
+    """The admin endpoint surfaces bounced rows alongside the rest;
+    filtering by `status=bounced` isolates them."""
+    from fastapi.testclient import TestClient
+    from app import db, email as email_mod
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=802, login="adminB", role="admin")
+        sign_in_as(
+            client, user_id=802, gitea_login="adminB",
+            display_name="Admin B", role="admin", email="adminb@test",
+        )
+        email_mod.reset_sent_envelopes()
+        client.post("/auth/otc/request", json={"email": "willbounce@ex.co"})
+        row = db.conn().execute(
+            "SELECT message_id FROM outbound_emails WHERE to_address = 'willbounce@ex.co'"
+        ).fetchone()
+        client.post(
+            "/api/webhooks/email-bounce",
+            json={"email": "willbounce@ex.co", "kind": "hard", "message_id": row["message_id"]},
+        )
+
+        r = client.get("/api/admin/outbound-emails?status=bounced")
+        assert r.status_code == 200
+        items = r.json()["items"]
+        assert items
+        assert all(it["status"] == "bounced" for it in items)
+        assert any(it["to_address"] == "willbounce@ex.co" for it in items)

backend/tests/test_pr_flow_vertical.py

@@ -21,6 +21,7 @@ import pytest
 from test_propose_vertical import (  # noqa: F401
     FakeGitea,
     app_with_fake_gitea,
+    grant_rfc_collaborator,
     provision_user_row,
     sign_in_as,
     tmp_env,
@@ -140,6 +141,9 @@ def test_get_pr_returns_three_column_payload(app_with_fake_gitea):
         provision_user_row(user_id=3, login="bob", role="contributor")
         seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
         # Bob is the non-arbiter contributor — alice is seeded as an RFC owner.
+        # v0.16.0 (item #12): bob needs an accepted per-RFC contributor
+        # invitation to cut branches and open PRs on alice's RFC.
+        grant_rfc_collaborator(user_id=3, rfc_slug="ohm", role_in_rfc="contributor")
         sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob", role="contributor")
         branch, _ = _cut_branch_and_accept_change(
             client, fake, slug="ohm",
@@ -292,6 +296,9 @@ def test_merge_by_arbiter_advances_main_and_marks_pr_merged(app_with_fake_gitea)
         provision_user_row(user_id=1, login="ben", role="owner")
         seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
         # Bob is neither owner nor arbiter — the non-merge baseline.
+        # v0.16.0 (item #12): bob still needs an accepted contributor
+        # invitation to cut the branch + open the PR.
+        grant_rfc_collaborator(user_id=3, rfc_slug="ohm", role_in_rfc="contributor")
         sign_in_as(client, user_id=3, gitea_login="bob", display_name="Bob", role="contributor")
         branch, _ = _cut_branch_and_accept_change(
             client, fake, slug="ohm",
@@ -364,6 +371,10 @@ def test_resolution_branch_replays_clean_and_supersedes_on_merge(app_with_fake_g
         provision_user_row(user_id=3, login="bob", role="contributor")
         provision_user_row(user_id=1, login="ben", role="owner")
         seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
+        # v0.16.0 (item #12): bob (a non-owner contributor) needs an
+        # accepted per-RFC invitation to cut a branch on alice's RFC.
+        # Alice is the seeded RFC owner so she doesn't need one.
+        grant_rfc_collaborator(user_id=3, rfc_slug="ohm", role_in_rfc="contributor")
 
         # Alice cuts a branch and accepts a change on it.
         sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor")

backend/tests/test_project_scoped_propose.py

@@ -0,0 +1,79 @@
+"""§22.4 (Plan B write): proposing a new entry into a *specific* project lands
+it in that project's content repo and surfaces under that project's proposals,
+isolated from the default project."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _register_ecomm(fake):
+    from app import db
+    db.conn().execute(
+        "INSERT OR IGNORE INTO projects (id, name, content_repo, visibility) "
+        "VALUES ('ecomm', 'Ecomm', 'ecomm-content', 'public')"
+    )
+    db.conn().execute(
+        "INSERT OR IGNORE INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES ('ecomm', 'ecomm', 'document', '', 'super-draft', 'public', 'Ecomm')"
+    )
+    fake._seed_repo("wiggleverse", "ecomm-content")
+
+
+def test_propose_into_second_project_lands_scoped(app_with_fake_gitea):
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        _register_ecomm(fake)
+        provision_user_row(user_id=3, login="alice", role="contributor")
+        # §22 S3: the grandfathered implicit-public baseline covers only the N=1
+        # `default` collection; a second project requires an explicit scope grant
+        # to write. Grant alice contributor at the ecomm project.
+        from app import db
+        db.conn().execute(
+            "INSERT OR REPLACE INTO memberships (scope_type, scope_id, user_id, role) "
+            "VALUES ('project', 'ecomm', 3, 'contributor')")
+        sign_in_as(client, user_id=3, gitea_login="alice", display_name="Alice",
+                   role="contributor", email="alice@test")
+        r = client.post("/api/projects/ecomm/rfcs/propose", json={
+            "title": "Cart", "slug": "cart", "pitch": "why a cart", "tags": [],
+        })
+        assert r.status_code == 200, r.text
+
+        # The idea PR shows under ecomm's proposals, not the default's.
+        e = {i["slug"] for i in client.get("/api/projects/ecomm/proposals").json()["items"]}
+        d = {i["slug"] for i in client.get("/api/projects/default/proposals").json()["items"]}
+        assert "cart" in e
+        assert "cart" not in d
+
+        # It landed in ecomm's content repo, not the default 'meta' repo.
+        assert ("wiggleverse", "ecomm-content") in {
+            (o, rp) for (o, rp) in fake.branches if rp == "ecomm-content"
+        }
+        assert any(
+            br.startswith("propose/cart")
+            for br in fake.branches.get(("wiggleverse", "ecomm-content"), {})
+        )
+
+
+def test_propose_into_gated_project_404s_for_non_member(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    from app import db
+    with TestClient(app) as client:
+        db.conn().execute(
+            "INSERT OR IGNORE INTO projects (id, name, content_repo, visibility) "
+            "VALUES ('secret', 'Secret', 'secret-content', 'gated')"
+        )
+        db.conn().execute(
+            "INSERT OR IGNORE INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+            "VALUES ('secret', 'secret', 'document', '', 'super-draft', 'gated', 'Secret')"
+        )
+        provision_user_row(user_id=4, login="bob", role="contributor")
+        sign_in_as(client, user_id=4, gitea_login="bob", display_name="Bob",
+                   role="contributor", email="bob@test")
+        r = client.post("/api/projects/secret/rfcs/propose", json={
+            "title": "X", "slug": "x", "pitch": "p", "tags": [],
+        })
+        assert r.status_code == 404

backend/tests/test_project_scoped_serving.py

@@ -0,0 +1,74 @@
+"""§22.4 (Plan B) — per-project RFC serving. A second project's corpus renders
+under its own slug namespace via /api/projects/{pid}/rfcs[/{slug}], isolated
+from the default project and gated by §22.5 visibility."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import (  # noqa: F401
+    app_with_fake_gitea, tmp_env, provision_user_row, sign_in_as,
+)
+
+
+def _add_project(pid, name, vis="public"):
+    # §22 three-tier: a project + its default collection (keyed by the project
+    # id in tests, so default_collection_id(pid) == pid).
+    from app import db
+    db.conn().execute(
+        "INSERT OR IGNORE INTO projects (id, name, content_repo, visibility) VALUES (?, ?, ?, ?)",
+        (pid, name, pid + "-content", vis),
+    )
+    db.conn().execute(
+        "INSERT OR IGNORE INTO collections (id, project_id, type, subfolder, initial_state, visibility, name) "
+        "VALUES (?, ?, 'document', '', 'super-draft', ?, ?)",
+        (pid, pid, vis, name),
+    )
+
+
+def _add_rfc(slug, title, pid, state="active"):
+    from app import db
+    # entries key by the project's default collection (id == pid in these tests)
+    db.conn().execute(
+        "INSERT INTO cached_rfcs (slug, title, state, collection_id) VALUES (?, ?, ?, ?)",
+        (slug, title, state, pid),
+    )
+
+
+def test_catalog_scoped_to_one_project(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("ecomm", "Ecomm")
+        _add_rfc("intro", "Default Intro", "default")
+        _add_rfc("intro", "Ecomm Intro", "ecomm")
+        _add_rfc("only-ecomm", "Ecomm Only", "ecomm")
+
+        d = client.get("/api/projects/default/rfcs").json()["items"]
+        e = client.get("/api/projects/ecomm/rfcs").json()["items"]
+        d_slugs = {i["slug"] for i in d}
+        e_slugs = {i["slug"] for i in e}
+        assert "intro" in d_slugs and "only-ecomm" not in d_slugs
+        assert {"intro", "only-ecomm"} <= e_slugs
+
+
+def test_entry_is_isolated_by_project(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("ecomm", "Ecomm")
+        _add_rfc("intro", "Default Intro", "default")
+        _add_rfc("intro", "Ecomm Intro", "ecomm")
+        _add_rfc("only-ecomm", "Ecomm Only", "ecomm")
+
+        assert client.get("/api/projects/default/rfcs/intro").json()["title"] == "Default Intro"
+        assert client.get("/api/projects/ecomm/rfcs/intro").json()["title"] == "Ecomm Intro"
+        # a slug that exists only in ecomm 404s under default
+        assert client.get("/api/projects/ecomm/rfcs/only-ecomm").status_code == 200
+        assert client.get("/api/projects/default/rfcs/only-ecomm").status_code == 404
+
+
+def test_gated_project_catalog_404s_for_anon(app_with_fake_gitea):
+    app, _ = app_with_fake_gitea
+    with TestClient(app) as client:
+        _add_project("secret", "Secret", vis="gated")
+        _add_rfc("hush", "Hush", "secret")
+        assert client.get("/api/projects/secret/rfcs").status_code == 404
+        assert client.get("/api/projects/secret/rfcs/hush").status_code == 404

backend/tests/test_propose_vertical.py

@@ -55,6 +55,24 @@ class FakeGitea:
         self._pr_counter = 0
         self._commit_counter = 0
         self._seed_repo("wiggleverse", "meta")
+        # §22 M3: the deployment's project registry. Startup refresh_registry
+        # reads projects.yaml here; the single 'default' project's content_repo
+        # points back at the seeded meta repo so the corpus mirror is unchanged.
+        self._seed_repo("wiggleverse", "registry")
+        self.files[("wiggleverse", "registry", "main", "projects.yaml")] = {
+            "content": (
+                "deployment:\n"
+                "  name: Test Deployment\n"
+                "  tagline: A test deployment\n"
+                "projects:\n"
+                "  - id: default\n"
+                "    name: Test Deployment\n"
+                "    type: document\n"
+                "    content_repo: meta\n"
+                "    visibility: public\n"
+            ),
+            "sha": "regsha0001",
+        }
 
     def _seed_repo(self, owner, repo):
         self.branches[(owner, repo)] = {"main": {"sha": "initial", "ts": "2026-05-23T00:00:00Z"}}
@@ -72,6 +90,28 @@ class FakeGitea:
         self._commit_counter += 1
         return f"sha{self._commit_counter:04d}"
 
+    def _dir_listing(self, owner, repo, ref, dirpath):
+        """Children directly under `dirpath` on (owner, repo, ref): files as
+        `type: file` and immediate subdirectories as `type: dir` (the shape real
+        Gitea returns for a contents listing)."""
+        prefix = (dirpath.rstrip("/") + "/") if dirpath else ""
+        files: dict[str, dict] = {}
+        dirs: set[str] = set()
+        for (o, r, br, p), data in self.files.items():
+            if (o, r, br) != (owner, repo, ref) or not p.startswith(prefix):
+                continue
+            rest = p[len(prefix):]
+            if "/" in rest:
+                dirs.add(rest.split("/", 1)[0])
+            elif rest:
+                files[p] = data
+        children = [{"name": n, "path": prefix + n, "type": "dir"} for n in sorted(dirs)]
+        children += [
+            {"name": p.rsplit("/", 1)[-1], "path": p, "type": "file", "sha": d["sha"]}
+            for p, d in sorted(files.items())
+        ]
+        return children
+
     def _enrich_pr(self, owner: str, repo: str, pr: dict) -> dict:
         """Return the PR with mergeability fields filled in.
 
@@ -209,6 +249,16 @@ class FakeGitea:
             }
             return httpx.Response(201, json={"name": new})
 
+        # GET /repos/{owner}/{repo}/contents (root listing, empty path). §22 S2:
+        # the registry mirror walks the content-repo root for collection
+        # subfolders, so the simulator models a root directory listing that
+        # surfaces both file and `dir` children.
+        m_root = re.fullmatch(r"/repos/([^/]+)/([^/]+)/contents/?", path)
+        if method == "GET" and m_root:
+            owner, repo = m_root.groups()
+            ref = request.url.params.get("ref", "main")
+            return httpx.Response(200, json=self._dir_listing(owner, repo, ref, ""))
+
         # GET /repos/{owner}/{repo}/contents/{path}?ref=...
         m = re.fullmatch(r"/repos/([^/]+)/([^/]+)/contents/(.+)", path)
         if method == "GET" and m:
@@ -224,17 +274,8 @@ class FakeGitea:
                     "sha": f["sha"],
                     "content": base64.b64encode(f["content"].encode()).decode(),
                 })
-            # Directory listing
-            prefix = fpath.rstrip("/") + "/"
-            children = []
-            for (o, r, br, p), data in self.files.items():
-                if (o, r, br) == (owner, repo, ref) and p.startswith(prefix) and "/" not in p[len(prefix):]:
-                    children.append({
-                        "name": p.rsplit("/", 1)[-1],
-                        "path": p,
-                        "type": "file",
-                        "sha": data["sha"],
-                    })
+            # Directory listing — both file and subdir children.
+            children = self._dir_listing(owner, repo, ref, fpath)
             if children:
                 return httpx.Response(200, json=children)
             return httpx.Response(404, json={"message": "not found"})
@@ -395,6 +436,28 @@ def provision_user_row(*, user_id: int, login: str, role: str) -> None:
     )
 
 
+def grant_rfc_collaborator(*, user_id: int, rfc_slug: str, role_in_rfc: str = "contributor") -> None:
+    """v0.16.0 / item #12 test seam: directly insert an accepted-
+    invitation collaborator row so a non-owner contributor can pass
+    the per-RFC write gate without going through the email round-trip.
+
+    Equivalent in effect to the invitation→accept dance the production
+    code drives; lets v0.5.0/v0.6.0/v0.8.0 era tests preserve their
+    "alice owns OHM, bob contributes" shape without rewriting the
+    setup. The invitation_id is left NULL — collaborators minted via
+    a direct admin gesture (a §19.2 candidate) carry the same shape.
+    """
+    from app import db
+    db.conn().execute(
+        """
+        INSERT OR REPLACE INTO rfc_collaborators
+            (rfc_slug, user_id, role_in_rfc, invitation_id)
+        VALUES (?, ?, ?, NULL)
+        """,
+        (rfc_slug, user_id, role_in_rfc),
+    )
+
+
 # ---------------------------------------------------------------------------
 # Fixtures
 # ---------------------------------------------------------------------------
@@ -409,15 +472,31 @@ def tmp_env(monkeypatch):
         "GITEA_BOT_USER": "rfc-bot",
         "GITEA_BOT_TOKEN": "bot-token",
         "GITEA_ORG": "wiggleverse",
-        "META_REPO": "meta",
+        "REGISTRY_REPO": "registry",
         "OAUTH_CLIENT_ID": "cid",
         "OAUTH_CLIENT_SECRET": "csec",
         "APP_URL": "http://localhost:8000",
         "SECRET_KEY": "test-secret-key-for-cookies",
         "DATABASE_PATH": str(db_path),
         "OWNER_GITEA_LOGIN": "ben",
-        "GITEA_WEBHOOK_SECRET": "",
+        # v0.18.0: `GITEA_WEBHOOK_SECRET` is now mandatory at startup
+        # per the email + webhook hygiene proposal. Tests bind a fake
+        # value so the framework boots; tests that want to exercise
+        # the dev-bypass path monkeypatch `RFC_APP_INSECURE_WEBHOOKS=1`.
+        "GITEA_WEBHOOK_SECRET": "test-webhook-secret-for-signature-verification",
         "ENABLED_MODELS": "claude",
+        # v0.27.0 (audit 0026 M4): the session cookie now defaults to
+        # Secure. The TestClient talks plain http://testserver, so a
+        # Secure cookie is never sent back and every authenticated flow
+        # would fail. Tests opt out explicitly, exactly as a dev box on
+        # plain http does.
+        "SESSION_COOKIE_SECURE": "false",
+        # v0.27.0 (audit 0026 M5): the bounce webhook fails closed (503)
+        # when its secret is unset. Tests exercise the legacy behavioral
+        # path via the documented dev opt-in, mirroring the
+        # RFC_APP_INSECURE_WEBHOOKS bypass above. Tests that assert the
+        # fail-closed default delenv this key themselves.
+        "RFC_APP_INSECURE_BOUNCE_WEBHOOK": "1",
     }
     for k, v in env.items():
         monkeypatch.setenv(k, v)
@@ -539,6 +618,97 @@ def test_propose_to_super_draft_vertical(app_with_fake_gitea):
         assert ("merge_proposal", "ben") in kinds
 
 
+def test_merged_idea_pr_with_deleted_branch_clears_proposal(app_with_fake_gitea):
+    """Regression: a merged idea PR whose branch was deleted must not
+    linger as a 'pending idea' ghost.
+
+    Found via the ROADMAP #35 operator authoring lane: merging an idea
+    PR from the CLI with `--delete-branch` makes Gitea report the PR's
+    `head.ref` as the synthetic `refs/pull/<N>/head` sentinel instead of
+    `propose/<slug>`. `refresh_meta_pulls` derives the slug from the
+    branch name, so the sentinel parsed to slug=None, the row was skipped,
+    and `cached_prs.state` stayed frozen at 'open' — leaving the entry
+    showing as BOTH a super-draft (cached_rfcs reconciled off the push)
+    AND a pending idea (cached_prs never updated). The fix recovers the
+    original branch name from the already-stored cached_prs row.
+
+    The web UX never tripped this because it leaves the branch in place
+    (the repo's default_delete_branch_after_merge is false).
+
+    The bug only manifests on an out-of-band merge (the PR merged +
+    branch deleted directly in Gitea, with the in-app merge endpoint never
+    reconciling the row while the branch still existed) -- which is exactly
+    what the #35 CLI lane does. An in-app merge reconciles cached_prs to
+    'merged' before the branch is gone, so it never trips this; the test
+    therefore drives the Gitea state directly to reproduce the CLI path.
+    """
+    from fastapi.testclient import TestClient
+    from app import db, cache, gitea as gitea_mod
+    from app.config import load_config
+
+    app, fake = app_with_fake_gitea
+
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor", email="alice@test")
+        r = client.post("/api/rfcs/propose", json={
+            "title": "Informed Consent",
+            "slug": "informed-consent",
+            "pitch": "A first-class definition of consent in OHM.",
+            "tags": [],
+        })
+        assert r.status_code == 200, r.text
+        pr_number = r.json()["pr_number"]
+
+        # The proposal is cached as an open idea PR.
+        items = client.get("/api/proposals").json()["items"]
+        assert any(i["pr_number"] == pr_number for i in items)
+
+        # Out-of-band CLI merge (ROADMAP #35 lane): the PR is merged AND
+        # its branch deleted directly in Gitea, WITHOUT the in-app merge
+        # endpoint ever running. So cached_prs still says state='open' and
+        # Gitea now reports the merged PR's head.ref as the sentinel. This
+        # is the exact state `rfc-authoring.sh pr-merge --delete-branch`
+        # leaves behind.
+        for pr in fake.pulls[("wiggleverse", "meta")]:
+            if pr["number"] == pr_number:
+                # land the file on main (the push side already reconciles
+                # cached_rfcs into a super-draft via the webhook/sweep)
+                for (o, rp, br, p), data in list(fake.files.items()):
+                    if (o, rp, br) == ("wiggleverse", "meta", "propose/informed-consent"):
+                        fake.files[("wiggleverse", "meta", "main", p)] = dict(data)
+                pr["state"] = "closed"
+                pr["merged"] = True
+                pr["merged_at"] = "2026-05-29T12:13:00Z"
+                pr["closed_at"] = "2026-05-29T12:13:00Z"
+                pr["merge_commit_sha"] = fake._next_sha()
+                pr["head"]["ref"] = f"refs/pull/{pr_number}/head"
+        fake.branches[("wiggleverse", "meta")].pop("propose/informed-consent", None)
+
+        # The reconcile sweep runs (a later webhook, or the 5-min safety net).
+        import asyncio
+        cfg = load_config()
+        gclient = gitea_mod.Gitea(cfg)
+        asyncio.run(cache.refresh_meta_repo(cfg, gclient))
+        asyncio.run(cache.refresh_meta_pulls(cfg, gclient))
+
+        # The bug: this used to still list informed-consent (frozen 'open'
+        # row, slug unparseable from the sentinel). The fix recovers the
+        # stored branch name, so the row reconciles to merged and the ghost
+        # is gone.
+        assert client.get("/api/proposals").json()["items"] == []
+
+        # And the cached_prs row is correctly merged, not a frozen 'open'.
+        row = db.conn().execute(
+            "SELECT state FROM cached_prs WHERE pr_number = ?", (pr_number,)
+        ).fetchone()
+        assert row["state"] == "merged", f"expected merged, got {row['state']}"
+
+        # The super-draft itself is unaffected — still in the catalog.
+        items = client.get("/api/rfcs").json()["items"]
+        assert any(i["slug"] == "informed-consent" and i["state"] == "super-draft" for i in items)
+
+
 def test_slug_uniqueness_enforced(app_with_fake_gitea):
     from fastapi.testclient import TestClient
     app, _fake = app_with_fake_gitea

backend/tests/test_proposed_use_case_vertical.py

@@ -0,0 +1,161 @@
+"""End-to-end vertical for roadmap #26 (rfc-app v0.22.0): the optional
+"What will you be using this for?" capture on the two propose surfaces.
+
+Reuses the FakeGitea + session helpers from test_propose_vertical.py and
+the active-RFC seed from test_rfc_view_vertical.py. Proves:
+
+  (a) propose-RFC persists and returns `proposed_use_case` when supplied,
+      and the value survives onto the merged super-draft's RFC view;
+  (b) propose-RFC accepts a NULL / omitted use case ("left blank");
+  (c) propose-PR persists and returns `proposed_use_case` when supplied,
+      and accepts a NULL / omitted one.
+"""
+from __future__ import annotations
+
+from test_propose_vertical import (  # noqa: F401
+    FakeGitea,
+    app_with_fake_gitea,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+from test_pr_flow_vertical import _cut_branch_and_accept_change
+from test_rfc_view_vertical import SEED_BODY, seed_active_rfc
+
+
+# ---------------------------------------------------------------------------
+# propose-RFC
+# ---------------------------------------------------------------------------
+
+
+def test_propose_rfc_persists_and_returns_use_case(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        provision_user_row(user_id=1, login="ben", role="owner")
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor", email="alice@test")
+
+        r = client.post("/api/rfcs/propose", json={
+            "title": "Open Human Model",
+            "slug": "open-human-model",
+            "pitch": "A shared definition of what we mean by *human*.",
+            "tags": ["identity"],
+            "proposed_use_case": "Wiring OHM into the OpenXML consent surface.",
+        })
+        assert r.status_code == 200, r.text
+        pr_number = r.json()["pr_number"]
+
+        # The pending-idea list carries the use case.
+        items = client.get("/api/proposals").json()["items"]
+        assert items[0]["proposed_use_case"] == "Wiring OHM into the OpenXML consent surface."
+
+        # The pending-idea detail view carries it too.
+        proposal = client.get(f"/api/proposals/{pr_number}").json()
+        assert proposal["proposed_use_case"] == "Wiring OHM into the OpenXML consent surface."
+
+        # Merge as owner; the use case survives onto the RFC view (looked
+        # up by slug from the canonical side table, since the idea PR
+        # closes on merge).
+        sign_in_as(client, user_id=1, gitea_login="ben", display_name="Ben", role="owner", email="ben@test")
+        r = client.post(f"/api/proposals/{pr_number}/merge")
+        assert r.status_code == 200, r.text
+
+        view = client.get("/api/rfcs/open-human-model").json()
+        assert view["proposed_use_case"] == "Wiring OHM into the OpenXML consent surface."
+
+
+def test_propose_rfc_use_case_optional(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, _fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=3, login="carol", role="contributor")
+        sign_in_as(client, user_id=3, gitea_login="carol", display_name="Carol", role="contributor")
+
+        # Omitted entirely.
+        r = client.post("/api/rfcs/propose", json={
+            "title": "No Use Case", "slug": "no-use-case", "pitch": "p", "tags": [],
+        })
+        assert r.status_code == 200, r.text
+        pr_a = r.json()["pr_number"]
+
+        # Explicit null.
+        r = client.post("/api/rfcs/propose", json={
+            "title": "Null Use Case", "slug": "null-use-case", "pitch": "p",
+            "tags": [], "proposed_use_case": None,
+        })
+        assert r.status_code == 200, r.text
+        pr_b = r.json()["pr_number"]
+
+        # Blank/whitespace — treated as "left blank", no row written.
+        r = client.post("/api/rfcs/propose", json={
+            "title": "Blank Use Case", "slug": "blank-use-case", "pitch": "p",
+            "tags": [], "proposed_use_case": "   ",
+        })
+        assert r.status_code == 200, r.text
+        pr_c = r.json()["pr_number"]
+
+        for pr in (pr_a, pr_b, pr_c):
+            assert client.get(f"/api/proposals/{pr}").json()["proposed_use_case"] is None
+
+
+# ---------------------------------------------------------------------------
+# propose-PR (against an active RFC)
+# ---------------------------------------------------------------------------
+
+
+def test_propose_pr_persists_and_returns_use_case(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor")
+
+        branch, _ = _cut_branch_and_accept_change(
+            client, fake, slug="ohm",
+            original="Open Human Model is a framework for representing humans.",
+            proposed="Open Human Model is a framework for representing humans across systems.",
+        )
+        r = client.post(
+            f"/api/rfcs/ohm/branches/{branch}/open-pr",
+            json={
+                "title": "Tighten the opening",
+                "description": "Scope to systems.",
+                "proposed_use_case": "Building a cross-system consent registry.",
+            },
+        )
+        assert r.status_code == 200, r.text
+        pr_number = r.json()["pr_number"]
+
+        pr = client.get(f"/api/rfcs/ohm/prs/{pr_number}").json()
+        assert pr["proposed_use_case"] == "Building a cross-system consent registry."
+
+
+def test_propose_pr_use_case_optional(app_with_fake_gitea):
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="alice", role="contributor")
+        seed_active_rfc(fake, slug="ohm", title="OHM", body=SEED_BODY)
+        sign_in_as(client, user_id=2, gitea_login="alice", display_name="Alice", role="contributor")
+
+        branch, _ = _cut_branch_and_accept_change(
+            client, fake, slug="ohm",
+            original="It defines consent, trait, and agency in compatible terms.",
+            proposed="It defines consent, trait, harm, and agency in compatible terms.",
+        )
+        # No proposed_use_case key at all.
+        r = client.post(
+            f"/api/rfcs/ohm/branches/{branch}/open-pr",
+            json={"title": "Add harm", "description": "Name harm explicitly."},
+        )
+        assert r.status_code == 200, r.text
+        pr_number = r.json()["pr_number"]
+
+        pr = client.get(f"/api/rfcs/ohm/prs/{pr_number}").json()
+        assert pr["proposed_use_case"] is None

backend/tests/test_registry.py

@@ -0,0 +1,106 @@
+"""§22.2 registry parse + apply: validation, type-immutability, upsert."""
+from __future__ import annotations
+
+import tempfile
+from pathlib import Path
+
+import pytest
+
+from app import db, registry
+from app.config import Config
+
+
+def _db():
+    cfg = Config(
+        gitea_url="x", gitea_bot_user="x", gitea_bot_token="x", gitea_org="x",
+        registry_repo="registry", oauth_client_id="x",
+        oauth_client_secret="x", app_url="x", secret_key="x",
+        database_path=Path(tempfile.mkdtemp(prefix="reg-")) / "t.db",
+        owner_gitea_login="x", webhook_secret="x",
+    )
+    db.run_migrations(cfg)
+    if db._CONN is not None:
+        db._CONN.close()
+        db._CONN = None
+    db.init(cfg)
+    return cfg
+
+
+VALID = """
+deployment:
+  name: Open Human Model
+  tagline: A model of human flourishing
+projects:
+  - id: default
+    name: Open Human Model
+    type: document
+    content_repo: meta
+    visibility: public
+"""
+
+
+def test_parse_valid_registry():
+    doc = registry.parse_registry(VALID)
+    assert doc.deployment_name == "Open Human Model"
+    assert doc.deployment_tagline == "A model of human flourishing"
+    assert len(doc.projects) == 1
+    p = doc.projects[0]
+    assert (p.id, p.type, p.content_repo, p.visibility) == ("default", "document", "meta", "public")
+    assert p.initial_state == "super-draft"
+
+
+def test_parse_initial_state_defaults_per_type():
+    doc = registry.parse_registry(
+        "projects:\n  - {id: a, name: A, type: bdd, content_repo: a}\n"
+    )
+    assert doc.projects[0].initial_state == "active"  # bdd default
+
+
+@pytest.mark.parametrize("bad,msg", [
+    ("projects: []\n", "at least one"),
+    ("projects:\n  - just-a-string\n", "must be a mapping"),
+    ("projects:\n  - {id: 'Bad Slug', name: A, type: document, content_repo: a}\n", "valid slug"),
+    ("projects:\n  - {id: a, name: A, type: nope, content_repo: a}\n", "invalid type"),
+    ("projects:\n  - {id: a, name: A, type: document}\n", "content_repo"),
+    ("projects:\n  - {id: a, name: A, type: document, content_repo: a, visibility: x}\n", "visibility"),
+    ("projects:\n  - {id: a, name: A, type: document, content_repo: a}\n  - {id: a, name: B, type: document, content_repo: b}\n", "duplicate"),
+])
+def test_parse_rejects_invalid(bad, msg):
+    with pytest.raises(registry.RegistryError) as e:
+        registry.parse_registry(bad)
+    assert msg in str(e.value)
+
+
+def test_apply_upserts_projects_and_deployment():
+    _db()
+    doc = registry.parse_registry(VALID)
+    registry.apply_registry(doc, registry_sha="regsha1", default_id="default")
+    # §22 three-tier: the project carries the grouping-tier fields; the
+    # per-corpus type/initial_state live on its default collection.
+    prow = db.conn().execute(
+        "SELECT name, content_repo, visibility, registry_sha FROM projects WHERE id='default'"
+    ).fetchone()
+    assert prow["name"] == "Open Human Model"
+    assert prow["content_repo"] == "meta"
+    assert prow["registry_sha"] == "regsha1"
+    crow = db.conn().execute(
+        "SELECT type, initial_state FROM collections WHERE id='default'"
+    ).fetchone()
+    assert crow["type"] == "document"
+    assert crow["initial_state"] == "super-draft"
+    drow = db.conn().execute("SELECT name, tagline FROM deployment WHERE id=1").fetchone()
+    assert drow["name"] == "Open Human Model"
+    assert drow["tagline"] == "A model of human flourishing"
+
+
+def test_apply_rejects_type_change_on_existing_project():
+    _db()
+    registry.apply_registry(registry.parse_registry(VALID), "s1", default_id="default")
+    changed = VALID.replace("type: document", "type: specification")
+    registry.apply_registry(registry.parse_registry(changed), "s2", default_id="default")  # skipped
+    # §22.4a immutable type — now enforced on the collection.
+    t = db.conn().execute("SELECT type FROM collections WHERE id='default'").fetchone()["type"]
+    assert t == "document"  # immutable — unchanged
+    # The deployment row IS still advanced even though the type change was skipped.
+    drow = db.conn().execute("SELECT registry_sha FROM deployment WHERE id=1").fetchone()
+    assert drow["registry_sha"] == "s2"

backend/tests/test_registry_wiring.py

@@ -0,0 +1,54 @@
+"""Startup mirrors the registry; the registry webhook re-mirrors it."""
+from __future__ import annotations
+
+from fastapi.testclient import TestClient
+
+from test_propose_vertical import app_with_fake_gitea, tmp_env  # noqa: F401
+
+
+def test_startup_mirrors_registry_into_projects_and_deployment(app_with_fake_gitea):
+    from app import db
+
+    app, _ = app_with_fake_gitea
+    with TestClient(app):
+        prow = db.conn().execute(
+            "SELECT content_repo FROM projects WHERE id='default'"
+        ).fetchone()
+        assert prow["content_repo"] == "meta"   # from the registry, not META_REPO
+        # §22 three-tier: type now lives on the default collection.
+        crow = db.conn().execute(
+            "SELECT type FROM collections WHERE id='default'"
+        ).fetchone()
+        assert crow["type"] == "document"
+        drow = db.conn().execute("SELECT name FROM deployment WHERE id=1").fetchone()
+        assert drow["name"]  # deployment name mirrored from the registry
+
+
+def test_registry_webhook_remirrors(app_with_fake_gitea):
+    import hashlib
+    import hmac
+    import json as _json
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        from app import db
+        new_yaml = (
+            "deployment:\n  name: OHM\n  tagline: Edited tagline\n"
+            "projects:\n  - id: default\n    name: OHM\n    type: document\n"
+            "    content_repo: meta\n    visibility: public\n"
+        )
+        fake.files[("wiggleverse", "registry", "main", "projects.yaml")] = {
+            "content": new_yaml, "sha": "regsha2",
+        }
+        body = _json.dumps({"repository": {"full_name": "wiggleverse/registry"}}).encode()
+        secret = "test-webhook-secret-for-signature-verification"
+        sig = hmac.new(secret.encode(), body, hashlib.sha256).hexdigest()
+        r = client.post(
+            "/api/webhooks/gitea",
+            content=body,
+            headers={"X-Gitea-Event": "push", "X-Gitea-Signature": sig,
+                     "Content-Type": "application/json"},
+        )
+        assert r.status_code == 200
+        tagline = db.conn().execute("SELECT tagline FROM deployment WHERE id=1").fetchone()["tagline"]
+        assert tagline == "Edited tagline"

backend/tests/test_restamp_default_project.py

@@ -0,0 +1,69 @@
+"""§22.13 step 1 — the bootstrap-id re-stamp: 'default' → the configured
+DEFAULT_PROJECT_ID. §22 three-tier (S1): the entry-corpus tables key on
+collection_id now, so the re-stamp renames the *project grain* — the
+`collections.project_id` link and the denormalised project_id tags — while the
+entries stay in their collection. The stale 'default' projects row is dropped,
+the composite FKs stay intact, and it is idempotent."""
+from __future__ import annotations
+
+import tempfile
+from pathlib import Path
+
+import app.db as db
+from app import projects
+
+
+class _Cfg:
+    def __init__(self, path, default_id):
+        self.database_path = path
+        self.default_project_id = default_id
+
+
+def _setup(monkeypatch, default_id="ohm"):
+    path = str(Path(tempfile.mkdtemp()) / "t.db")
+    cfg = _Cfg(path, default_id)
+    db.run_migrations(cfg)  # seeds the bootstrap 'default' project + its default collection
+    monkeypatch.setattr(db, "_CONN", db.connect(path))
+    conn = db.conn()
+    # A registry-mirrored 'ohm' project coexists with the bootstrap pre-restamp.
+    conn.execute("INSERT OR IGNORE INTO projects (id,name,content_repo,visibility) "
+                 "VALUES ('ohm','Open Human Model','ohm-content','public')")
+    conn.execute("INSERT INTO users (id,gitea_login,display_name,role) VALUES (1,'a','A','contributor')")
+    # Entry data lives in the default collection (id='default'); the entry grain
+    # is the collection and does not move on a re-stamp.
+    conn.execute("INSERT INTO cached_rfcs (slug,title,state,collection_id) VALUES ('human','Human','active','default')")
+    conn.execute("INSERT INTO rfc_collaborators (rfc_slug,user_id,role_in_rfc,collection_id) "
+                 "VALUES ('human',1,'contributor','default')")
+    conn.execute("INSERT INTO stars (user_id,rfc_slug,collection_id) VALUES (1,'human','default')")
+    return cfg, conn
+
+
+def test_restamp_moves_project_grain_and_drops_bootstrap_row(monkeypatch):
+    cfg, conn = _setup(monkeypatch, default_id="ohm")
+    projects.restamp_default_project(cfg)
+    # The project grain (the collection's parent link) re-stamps to 'ohm'.
+    assert conn.execute("SELECT COUNT(*) c FROM collections WHERE project_id='default'").fetchone()["c"] == 0
+    assert conn.execute("SELECT project_id FROM collections WHERE id='default'").fetchone()["project_id"] == "ohm"
+    # Entries stay in their collection — the collection_id is unchanged.
+    assert conn.execute("SELECT collection_id FROM cached_rfcs WHERE slug='human'").fetchone()["collection_id"] == "default"
+    assert conn.execute("SELECT collection_id FROM rfc_collaborators WHERE rfc_slug='human'").fetchone()["collection_id"] == "default"
+    # stale bootstrap projects row removed; 'ohm' remains
+    assert conn.execute("SELECT 1 FROM projects WHERE id='default'").fetchone() is None
+    assert conn.execute("SELECT 1 FROM projects WHERE id='ohm'").fetchone() is not None
+    # FK integrity intact after the rename
+    assert conn.execute("PRAGMA foreign_key_check").fetchall() == []
+
+
+def test_restamp_is_idempotent(monkeypatch):
+    cfg, conn = _setup(monkeypatch, default_id="ohm")
+    projects.restamp_default_project(cfg)
+    projects.restamp_default_project(cfg)  # second call: no bootstrap rows left → no-op
+    assert conn.execute("SELECT project_id FROM collections WHERE id='default'").fetchone()["project_id"] == "ohm"
+    assert conn.execute("SELECT COUNT(*) c FROM cached_rfcs WHERE collection_id='default'").fetchone()["c"] == 1
+
+
+def test_restamp_noop_when_default_id_unchanged(monkeypatch):
+    cfg, conn = _setup(monkeypatch, default_id="")  # resolves to 'default'
+    projects.restamp_default_project(cfg)
+    # nothing renamed; the default collection still belongs to the bootstrap project
+    assert conn.execute("SELECT project_id FROM collections WHERE id='default'").fetchone()["project_id"] == "default"

backend/tests/test_retire_vertical.py

@@ -0,0 +1,257 @@
+"""End-to-end integration tests for the §13.7 retire (soft-delete) flow.
+
+Retire is an in-place frontmatter flip on the meta entry (state →
+`retired`) committed via an auto-merged PR — the same machinery as
+graduation, reused. The distinguishing rules under test:
+
+  * Authority (§3.1): RFC owners (frontmatter) and site `owner`-role
+    holders may retire; app admins may NOT. Un-retire is site-owners-only.
+  * Visibility (§13.7): a retired entry drops out of the catalog
+    (`GET /api/rfcs`), and `GET /api/rfcs/<slug>` 404s for everyone except
+    a site owner (so the un-retire affordance has a surface).
+  * Reversibility: a site owner can un-retire, restoring the prior state
+    (and keeping the integer id intact); an RFC owner cannot.
+
+These walk against the in-process FakeGitea from test_propose_vertical.py,
+reusing the super-draft seed + sync graduation seam from the graduation
+suite.
+"""
+from __future__ import annotations
+
+import json as _json
+
+from test_propose_vertical import (  # noqa: F401
+    FakeGitea,
+    app_with_fake_gitea,
+    grant_rfc_collaborator,
+    provision_user_row,
+    sign_in_as,
+    tmp_env,
+)
+from test_super_draft_vertical import seed_super_draft  # noqa: F401
+from test_graduation_vertical import PITCH, seed_owned_super_draft  # noqa: F401
+
+
+def _catalog_slugs(client) -> set[str]:
+    return {i["slug"] for i in client.get("/api/rfcs").json()["items"]}
+
+
+def test_rfc_owner_can_retire_and_entry_leaves_every_surface(app_with_fake_gitea):
+    """An RFC owner (frontmatter, role contributor) retires their own
+    super-draft. The entry flips to `retired`, drops out of the catalog,
+    and `GET /api/rfcs/<slug>` 404s for them (they are not a site owner)."""
+    from fastapi.testclient import TestClient
+    from app import db, entry as entry_mod
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"], arbiters=["carol"])
+        sign_in_as(client, user_id=2, gitea_login="carol",
+                   display_name="Carol", role="contributor")
+
+        assert "ohm" in _catalog_slugs(client)
+
+        r = client.post("/api/rfcs/ohm/retire")
+        assert r.status_code == 200, r.text
+        assert r.json()["state"] == "retired"
+
+        # Meta entry on main: state retired, body + fields kept.
+        meta = entry_mod.parse(
+            fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
+        )
+        assert meta.state == "retired"
+        assert "carol" in meta.owners
+
+        # Cache flipped; gone from the catalog.
+        cached = db.conn().execute(
+            "SELECT state FROM cached_rfcs WHERE slug = 'ohm'"
+        ).fetchone()
+        assert cached["state"] == "retired"
+        assert "ohm" not in _catalog_slugs(client)
+
+        # The RFC owner is NOT a site owner → 404 on the entry read.
+        assert client.get("/api/rfcs/ohm").status_code == 404
+
+        # Audit row records the prior state for un-retire.
+        row = db.conn().execute(
+            "SELECT details FROM actions WHERE rfc_slug='ohm' AND action_kind='retire' ORDER BY id DESC LIMIT 1"
+        ).fetchone()
+        assert row is not None
+        assert _json.loads(row["details"])["prior_state"] == "super-draft"
+
+
+def test_site_owner_sees_retired_entry_but_admin_and_others_404(app_with_fake_gitea):
+    """`GET /api/rfcs/<slug>` for a retired entry: site owner gets 200
+    (so the un-retire UI has a surface); an admin, a non-owner contributor,
+    and an anonymous viewer all get 404."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        provision_user_row(user_id=3, login="dave", role="admin")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+
+        sign_in_as(client, user_id=2, gitea_login="carol",
+                   display_name="Carol", role="contributor")
+        assert client.post("/api/rfcs/ohm/retire").status_code == 200
+
+        # Site owner: 200.
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner")
+        r = client.get("/api/rfcs/ohm")
+        assert r.status_code == 200, r.text
+        assert r.json()["state"] == "retired"
+
+        # Admin (not site owner): 404.
+        sign_in_as(client, user_id=3, gitea_login="dave",
+                   display_name="Dave", role="admin")
+        assert client.get("/api/rfcs/ohm").status_code == 404
+
+        # Non-owner contributor: 404.
+        provision_user_row(user_id=4, login="erin", role="contributor")
+        sign_in_as(client, user_id=4, gitea_login="erin",
+                   display_name="Erin", role="contributor")
+        assert client.get("/api/rfcs/ohm").status_code == 404
+
+
+def test_admin_cannot_retire(app_with_fake_gitea):
+    """§3.1: retire authority excludes app admins. An admin who is not an
+    RFC owner gets 403 — the one lifecycle action where admin authority
+    does not apply."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=3, login="dave", role="admin")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+        sign_in_as(client, user_id=3, gitea_login="dave",
+                   display_name="Dave", role="admin")
+        r = client.post("/api/rfcs/ohm/retire")
+        assert r.status_code == 403, r.text
+
+
+def test_non_owner_contributor_cannot_retire(app_with_fake_gitea):
+    """A signed-in contributor who is not an RFC owner gets 403."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=4, login="erin", role="contributor")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+        sign_in_as(client, user_id=4, gitea_login="erin",
+                   display_name="Erin", role="contributor")
+        assert client.post("/api/rfcs/ohm/retire").status_code == 403
+
+
+def test_site_owner_can_retire_active_and_unretire_restores_active_with_id(app_with_fake_gitea):
+    """Round-trip on an active RFC: graduate (with a number) → retire →
+    un-retire. The integer id survives, and un-retire restores `active`."""
+    from fastapi.testclient import TestClient
+    from app import db, entry as entry_mod
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["ben"], arbiters=["ben"])
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner", email="ben@test")
+
+        # Graduate with a number.
+        assert client.post("/api/rfcs/ohm/graduate?_sync=1",
+                           json={"rfc_id": "RFC-0042", "owners": ["ben"]}).status_code == 200
+
+        # Retire (site owner).
+        assert client.post("/api/rfcs/ohm/retire").json()["state"] == "retired"
+        assert "ohm" not in _catalog_slugs(client)
+
+        # Un-retire (site owner) restores active, id intact.
+        r = client.post("/api/rfcs/ohm/unretire")
+        assert r.status_code == 200, r.text
+        assert r.json()["state"] == "active"
+
+        meta = entry_mod.parse(
+            fake.files[("wiggleverse", "meta", "main", "rfcs/ohm.md")]["content"]
+        )
+        assert meta.state == "active"
+        assert meta.id == "RFC-0042"
+
+        cached = db.conn().execute(
+            "SELECT state, rfc_id FROM cached_rfcs WHERE slug = 'ohm'"
+        ).fetchone()
+        assert cached["state"] == "active"
+        assert cached["rfc_id"] == "RFC-0042"
+        assert "ohm" in _catalog_slugs(client)
+
+
+def test_rfc_owner_cannot_unretire(app_with_fake_gitea):
+    """Un-retire is site-owner-only: an RFC owner who could retire cannot
+    bring it back (the soft-delete is recoverable only by the operator)."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+        sign_in_as(client, user_id=2, gitea_login="carol",
+                   display_name="Carol", role="contributor")
+        assert client.post("/api/rfcs/ohm/retire").status_code == 200
+        # Same RFC owner tries to un-retire → 403.
+        assert client.post("/api/rfcs/ohm/unretire").status_code == 403
+
+
+def test_admin_retired_list_is_site_owner_only(app_with_fake_gitea):
+    """GET /api/admin/retired-rfcs lists retired entries for a site owner;
+    an admin (who lacks un-retire authority) gets 403."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=1, login="ben", role="owner")
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        provision_user_row(user_id=3, login="dave", role="admin")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+        sign_in_as(client, user_id=2, gitea_login="carol",
+                   display_name="Carol", role="contributor")
+        assert client.post("/api/rfcs/ohm/retire").status_code == 200
+
+        # Admin: 403.
+        sign_in_as(client, user_id=3, gitea_login="dave",
+                   display_name="Dave", role="admin")
+        assert client.get("/api/admin/retired-rfcs").status_code == 403
+
+        # Site owner: 200, sees ohm with its restore target.
+        sign_in_as(client, user_id=1, gitea_login="ben",
+                   display_name="Ben", role="owner")
+        r = client.get("/api/admin/retired-rfcs")
+        assert r.status_code == 200, r.text
+        items = r.json()["items"]
+        ohm = next(i for i in items if i["slug"] == "ohm")
+        assert ohm["restores_to"] == "super-draft"
+
+
+def test_retired_entry_refuses_discussion_reads(app_with_fake_gitea):
+    """A retired entry refuses content reads of every shape (§13.7) — the
+    discussion/branch surfaces 404/409 rather than serve a soft-deleted RFC."""
+    from fastapi.testclient import TestClient
+
+    app, fake = app_with_fake_gitea
+    with TestClient(app) as client:
+        provision_user_row(user_id=2, login="carol", role="contributor")
+        seed_owned_super_draft(fake, slug="ohm", title="OHM",
+                               pitch=PITCH, owners=["carol"])
+        sign_in_as(client, user_id=2, gitea_login="carol",
+                   display_name="Carol", role="contributor")
+        assert client.post("/api/rfcs/ohm/retire").status_code == 200
+
+        # The /main branch surface no longer serves it.
+        assert client.get("/api/rfcs/ohm/main").status_code in (404, 409)