0.12.20 0.12.21

Name: uv
Author: astral-sh

low risk

astral-sh/uvSep 28, 2026 → Sep 29, 20261 day between releases

What's New

Updates OpenSSL to 3.5.9 and improves lockfile cleanliness by omitting empty sections and redundant constraints

New Features

Omit empty `[manifest]` tables from lockfiles that contain only manifest subtables
Omit redundant runtime constraints from `uv.lock`, including those involving pre-releases, with the `resolution-inputs` preview feature

Improvements

Update CPython to use OpenSSL 3.5.9

Bug Fixes

Prevent `uv python pin --rm` from removing a global `.python-versions` file without `--global`
Fix installed-package checks incorrectly reporting post-releases as incompatible with exclusive lower bounds on pre-releases

Upgrade Notes

Lockfiles will be cleaner with empty sections and redundant constraints removed. The OpenSSL update improves security. No configuration changes are required.

The Two Releases

0.12.20

Sep 28, 2026· 23 days ago

This release focuses on lockfile optimization, encoding fixes for wheel scripts, and stability improvements including performance restoration for HTTP caching and bug fixes for hash constraints and panics.

Full release notes

0.12.21

Sep 29, 2026· 22 days ago

Updates CPython to use OpenSSL 3.5.9 and improves lockfile cleanliness by omitting empty sections and redundant constraints.

Full release notes