clean up

README.md

@@ -21,6 +21,22 @@ frontend collects the key on a login screen and the backend validates it.
 
 ## Quick start
 
+### With Docker (dev)
+
+Runs both services with hot-reload — the frontend on Vite, the backend on
+`uvicorn --reload`, each with its source volume-mounted from the host.
+
+```bash
+cp backend/.env.example backend/.env   # edit DB credentials + API_KEY
+docker compose up --build              # frontend :5173, backend :8000
+```
+
+The frontend proxies `/api/*` to the `backend` service over the compose
+network, so log in at http://localhost:5173 with the `API_KEY` from
+`backend/.env`.
+
+### Manual
+
 **Backend** (see [`backend/README.md`](backend/README.md) for details):
 
 ```bash