Steps to replicate the issue (include links if applicable):
- toolforge build start -L https://github.com/cluebotng/reviewer.git
What happens?:
[step-build] 2025-10-23T12:05:22.826024957Z [Determining Python version] [step-build] 2025-10-23T12:05:22.832611993Z [step-build] 2025-10-23T12:05:22.832653322Z [Error: The requested Python version isn't recognised] [step-build] 2025-10-23T12:05:22.832665448Z The requested Python version 3.14 isn't recognised. [step-build] 2025-10-23T12:05:22.832674207Z [step-build] 2025-10-23T12:05:22.832682719Z Check that this Python version has been officially released, [step-build] 2025-10-23T12:05:22.832690867Z and that the Python buildpack has added support for it: [step-build] 2025-10-23T12:05:22.832699037Z https://devguide.python.org/versions/#supported-versions [step-build] 2025-10-23T12:05:22.832707853Z https://devcenter.heroku.com/articles/python-support#supported-python-versions [step-build] 2025-10-23T12:05:22.832722003Z [step-build] 2025-10-23T12:05:22.832730194Z If it has, make sure that you are using the latest version [step-build] 2025-10-23T12:05:22.832739165Z of this buildpack, and haven't pinned to an older release [step-build] 2025-10-23T12:05:22.832747222Z via a custom buildpack configuration in project.toml. [step-build] 2025-10-23T12:05:22.832755274Z [step-build] 2025-10-23T12:05:22.832763200Z Otherwise, switch to a supported version (such as Python 3.13) [step-build] 2025-10-23T12:05:22.832772080Z by changing the version in your .python-version file. [step-build] 2025-10-23T12:05:22.832845569Z [step-build] 2025-10-23T12:05:22.834087119Z ERROR: failed to build: exit status 1
What should have happened instead?:
Image should build and does so in the upstream pack (as used in the upstream builder, as is executed in CI).
Other information (browser name/version, screenshots, etc.):
Python 3.14 was released over 2 weeks ago and is the current stable version (https://docs.python.org/3/whatsnew/3.14.html)
Support in the upstream pack was added 2 weeks ago (https://github.com/heroku/buildpacks-python/pull/442)
[step-detect] 2025-10-23T12:11:36.003117452Z heroku/python 0.26.1 is from 6 months ago