There are two main issues with python’s packaging tooling: There is no sane way to distribute python-written apps, in a way that guarantees that all dependencies (including C and Fortran-written OS-level dependencies) and a way to manage the dependencies of your python apps.
In particular, in-the-wild requirements.pip are neither OS-aware neither python-version aware. Maybe with Python 3.9 I want a set of dependencies, and with Python 3.13 I want another. This becomes relevant when dealing with multiple (api-breaking) numpy and other scientific packages.
Astral released a new uv version that tries to solidify the ecosystem, replacing all the usual, incomplete suspects (poetry, pip-tools, etc..). Their newish goal with uv is to become Python’s cargo. With uv, you can now create and run projects, execute standalone python tools on your OS (replacing pipx) and managing different python versions.
But one of my favorite features is the support for PEP 723, which allows you to include dependencies in single-file python scripts:
#!/usr/bin/env uv run
# /// script
# requires-python = ">=3.12"
# dependencies = [
# "flask==3.*",
# ]
# ///
import flask
# ...(via Simon Willison)