Idea: Specify python version constraints on optional dependencies in a pyproject.toml

[petersuter]

Requires-Python upper limits

Requires-Python upper limits Requires-Python was added to allow older versions of Python to be dropped by packages without breaking installation on older versions of Python. Currently (and for the last 4+ years), pip handles this quite simply; Requires-Python is a free-form SpecifierSet, and it checks to see if the current version of Python is included in the set. If not, it starts going back through a package’s history to find the most recent passing version. This was prompted by IPython droppi…

Requires-python and pre-release Python versions?

Currently both pip and uv (and others?) ignore the pre-release section of requires-python. E.g. [project] name = "foo" version = "0.1.0" requires-python = ">=3.13" [build-system] requires = ["setuptools", "wheel"] build-backend = "setuptools.build_meta" Using any Python 3.13 pre-release: $ pip install --dry-run . Processing ... Installing build dependencies ... done Getting requirements to build wheel ... done Preparing metadata (pyproject.toml) ... done Would install foo-0.1.0 Yet t…