Python This Week — August 17, 2026: uv 0.10, the 3.15 Home Stretch, and a New Packaging Council

A quieter follow-up week after the big early-August wave of releases, but there's still plenty moving: Astral shipped a breaking uv 0.10, Python 3.15 is deep in its release-candidate run, the Python Software Foundation named candidates for the first-ever Packaging Council, Polars kept pushing on performance, and the community calendar is filling up. Here's what mattered over the past week.

uv 0.10 lands with stabilized Python management — and a few breaking changes

Astral's Rust-based package manager reached the 0.10 line, its first minor bump since 0.9.0 last October, gathering up correctness fixes that could break some workflows. The headline is that Python version management is now stable: uv python upgrade, uv python install --upgrade, and automatic patch upgrades in virtual environments have all graduated out of preview, along with the add-bounds and workspace utilities. Watch the breaking changes if you upgrade: uv venv now needs --clear to overwrite an existing environment, uv errors when more than one index is marked as default, and explicit indexes must be referenced by name. source

Python 3.15 enters the home stretch

Python 3.15.0rc1 is out and the release is now in its candidate phase, where only clearly-safe bug fixes are accepted. The second and final candidate, 3.15.0rc2, is scheduled for September 1, with no further ABI changes from here, and the final 3.15.0 release is targeted for October 1. If you maintain libraries, now is the time to test against the release candidates and report anything that breaks. source

PSF names candidates for the inaugural Python Packaging Council

Following the approval of PEP 772, the Python Software Foundation announced the slate for the first-ever Python Packaging Council election: 17 nominees are competing for 5 seats. The two top vote-getters take two-year "Cohort A" terms and the next three take one-year "Cohort B" terms. Voting members must affirm their intent to vote by August 25, with balloting running September 1–15. This is a milestone for putting packaging governance on a formal, elected footing. source

Polars keeps sharpening performance

The Polars team's early-August release notes highlight more work on speed and interoperability, including streaming outer joins, zero-copy NumPy interop, a COUNT(*) fast path, and faster boolean filters and ternary operations. It's a continuation of a busy year for the DataFrame library, which shipped a steady stream of releases through the first half of 2026. source

On the calendar: CircuitPython Day and PyCon AU

Two dates for the community diary. Adafruit has declared August 21 — the "snakiest" day of the year — as CircuitPython Day, a celebration of Python on microcontrollers. And PyCon AU 2026 runs August 26–30, bringing the Australian Python community together for talks and sprints. source

That's the week in Python — see you next time.