Add compose-based backend runtime on python 3.14

README.md

@@ -9,8 +9,17 @@ Two separate Python packages live here:
 
 The repo also includes a Gitea Actions workflow at `.gitea/workflows/ci.yml` that tests and builds both packages on pushes to `main` and pull requests.
 
-## Backend setup
+## Docker backend (no image build)
 
+Run the backend directly from an official Python image without creating a Dockerfile:
+
+```bash
+docker compose up backend
+```
+
+This uses `python:3.14-slim`, installs `ffmpeg` and `openai-whisper` at container startup, mounts this repo into the container, and serves the API on `http://localhost:8000`.
+
+## Backend setup
 ```bash
 cd backend
 pip install -e .
@@ -50,3 +59,4 @@ whisper-remote ./audio.mp3 --model base --language en --output-format txt
 - backend-side cleanup of uploaded and generated files after each request
 
 By default the CLI prints the returned transcript to stdout. Use `--to-file` to save it locally.
+