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Python

A project with requirements.txt, pyproject.toml or Pipfile in its root is built as Python. Railpack picks the Python version, package manager and start command from the project's files; see Railpack: Python. Add a .python-version file to pin the version.

Example​

main.py
from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def index():
    return {"hello": "freepod"}
requirements.txt
fastapi
uvicorn

Railpack starts this example with uvicorn main:app on $PORT.

Start command​

If Railpack does not detect the start command, or detects the wrong one, set it in a Procfile. Bind to 0.0.0.0:$PORT:

Procfile
web: gunicorn --bind 0.0.0.0:$PORT app:app

Migrations​

Run migrations in the start command, before the server starts:

Procfile
web: sh -c 'alembic upgrade head && uvicorn main:app --host 0.0.0.0 --port $PORT'