diff --git a/Makefile b/Makefile
index 96a947e..d663205 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,11 @@
 .PHONY: sim sim-local
 
+# Prefer the project venv's interpreter (this box has no bare `python` on PATH),
+# fall back to python3, then python.
+PYTHON ?= $(firstword $(wildcard .venv/bin/python) python3 python)
+
 sim:
 	docker compose -f simulator/docker-compose.yml up --build
 
 sim-local:
-	python -m uvicorn simulator.app:app --reload --port 8000
+	$(PYTHON) -m uvicorn simulator.app:app --reload --port 8000