uv/docs/reference/policies/python.md

Python support

Python versions

uv supports and is tested against the following Python versions:

• 3.8
• 3.9
• 3.10
• 3.11
• 3.12
• 3.13
• 3.14
• 3.15

Python implementations

uv has Tier 1 support for the following Python implementations:

• CPython

As with platforms, Tier 1 support can be thought of "guaranteed to work". uv supports managed installations of these implementations, and the builds are maintained by Astral.

uv has Tier 2 support for:

• PyPy
• GraalPy

uv is "expected to work" with these implementations. uv also supports managed installations of these Python implementations, but the builds are not maintained by Astral.

uv has Tier 3 support for:

• Pyston
• Pyodide

uv "should work" with these implementations, but stability may vary.