You can specify requirements at the top of file and uv can run the script after automatically installing the dependencies.

https://avilpage.com/2025/04/learn-python-uv-in-100-seconds....

▲ simonw 2 days ago | parent | next [-]

This works really well in my experience, but it does mean you need to have a working internet connection the first time you run the script.

  # /// script
  # dependencies = [
  #     "cowsay",
  # ]
  # ///
  import cowsay
  cowsay.cow("Hello World")

Then:

  uv run cowscript.py

It manages a disposable hidden virtual environment automatically, via a very fast symlink-based caching mechanism.

You can also add a shebang line so you can execute it directly:

  #!/usr/bin/env -S uv run --script
  #
  # /// script
  # dependencies = ["cowsay"]
  # ///
  import cowsay
  cowsay.cow("Hello World")

Then:

  chmod 755 cowscript
  ./cowscript

▲ emidln 2 days ago | parent [-]

I wish env -S was more portable. It's a newer feature of the coreutils env implementation and isn't supported elsewhere afaik.

	▲	networked 9 hours ago \| parent \| next [-]
		You can use so-called "exec magic" instead of `env -S`. Here is an explanation with Python examples: https://dbohdan.com/scripts-with-dependencies#exec-magic (disclosure: my site). In short: `#! /bin/sh "exec" "/usr/bin/env" "uv" "run" "--quiet" "--script" "$0" "$@" # /// script # dependencies = [ # "cowsay", # ] # /// import cowsay cowsay.cow("Hello, world!")` On systems that can't run uv, like NetBSD and OpenBSD, switch to pipx: `#! /bin/sh "exec" "/usr/bin/env" "pipx" "run" "$0" "$@" # ...`
	▲	collinfunk 2 days ago \| parent \| prev [-]
		FreeBSD 6.0 added 'env -S'. They have adopted a few different GNU inspired options recently, which I am happy about.

▲ presbyterian 2 days ago | parent | prev [-]

As someone who writes a lot of python, I love uv, but isn't on nearly every system like python is, which is one of the arguments for using python here in the first place

	▲	ewidar 11 hours ago \| parent [-]
		Sure but the sub question here was about packages. If you are installing packages, then starting with installing uv should be fine.