Using uv as your shebang line
I create a fair few scripts in my ~/bin/ directory to automate tasks. Since discovering uv and inline script metadata, I’ve started using Python far more for these.
As ~/bin is on my path, I want to run the script by calling it directly on the command line. To do this, I use this shebang:
#!/usr/bin/env -S uv run --script
The command line will now run uv run --script and pass the file as the argument. uv ignores the shebang and then runs the rest of the file as a normal Python file.
Once I’ve ensured that that script has executable permissions via chmod a+x {filname}, I’m now good to go with simple command line scripts written in Python that automatically handle their dependencies!
This is indeed a cool feature. But it actually gets cooler!
If your Python script has dependencies, you can declare them in a fenced code block in a leading comment and uv will parse and install those in a temp venv before invoking the script!
For example:
#!/usr/bin/env -S uv run --script# /// script
# requires-python = ">=3.12"
# dependencies = [
# "ffmpeg-normalize",
# ]
# ///
That’s not my example I just copied it from https://treyhunner.com/2024/12/lazy-self-installing-python-scripts-with-uv/ which you should definitely read to learn more.
Yes. I linked to my post about PEP-723 in the first line of the post 😉