Shebang for Python virtual env

env

Addendum

• Install uv on Linux/MacOS
  • curl -LsSf https://astral.sh/uv/install.sh | sh
• Install uv on Windows
  • powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

Using pip/pipx

pip install uv
pipx install uv

Main post

#!/usr/bin/env -S uv run (via) This is a really neat pattern. Start your Python script like this:

#!/usr/bin/env -S uv run
# /// script
# requires-python = ">=3.12"
# dependencies = [
#     "flask==3.*",
# ]
# ///
import flask
# ...

And now if you chmod 755 it you can run it on any machine with the uv binary installed like this: ./app.py - and it will automatically create its own isolated environment and run itself with the correct installed dependencies and even the correctly installed Python version.

All of that from putting uv run in the shebang line!

Code from this PR by David Laban.