Python 3.15.0 added to actions/python-versions
- ID
- 34143
- Status
- summarized
- Published
- 11 Oct 2026, 7:58 AM
- Fetched
- 11 Oct 2026, 9:06 AM
- Provider
- Simon Willison
- Category
- developer-ai
- Original URL
- https://simonwillison.net/2026/Oct/10/python-actions/
- Source URL
- https://simonwillison.net/atom/everything/
Summary
- Score
- 4.0
- Created
- 11 Oct 2026, 9:06 AM
- Tags
- Audience
- developersvibe_coders
What happened
Simon Willison's link post notes that Python 3.15.0 has been added to the actions/python-versions repository, the manifest GitHub Actions' setup-python reads to resolve Python versions. That means "3.15" can now be dropped into a GitHub Actions testing matrix to run CI against the stable 3.15.0 release. Willison says he had ChatGPT poll the repo hourly for the addition so he'd be told when it landed.
Why it matters
If you run Python tests on GitHub Actions, the concrete change is that a matrix entry of "3.15" now resolves instead of failing, so you can add stable 3.15 coverage to CI without pinning a pre-release. It is a small operational unblock, not a decision that forces a migration; nothing in the post suggests 3.15 is required for existing projects.
Discussion angle
Is adding the newest stable Python to your CI matrix on day one worth it, or do you deliberately lag a release behind — and is having an agent poll a repo for a version bump a workflow you'd actually keep?