v281

• The Python 3.13 version alias now resolves to Python 3.13.3. (#1775)
• The Python 3.12 version alias now resolves to Python 3.12.10. (#1775)
• The Python 3.11 version alias now resolves to Python 3.11.12. (#1775)
• The Python 3.10 version alias now resolves to Python 3.10.17. (#1775)
• The Python 3.9 version alias now resolves to Python 3.9.22. (#1775)

v280

• Updated pip from 24.3.1 to 25.0.1. (#1759)
• Updated Poetry from 2.1.1 to 2.1.2. (#1772)

v279

• Updated Poetry from 2.0.1 to 2.1.1. (#1758)
• Stopped filtering out pip's Requirement already satisfied: log lines when installing dependencies. (#1765)
• Improved the error messages shown if installing pip/Poetry/Pipenv fails. (#1764)
• Stopped installing pip into Poetry's virtual environment. (#1761)

v278

• Added build-time rewriting of editable VCS dependency paths (in addition to the existing run-time rewriting), to work around an upstream Pipenv bug with editable VCS dependencies not being reinstalled correctly for cached builds. (#1756)
• Changed the location of repositories for editable VCS dependencies when using pip and Pipenv, to improve build performance and match the behaviour when using Poetry. (#1753)

v277

• Improved the warning message shown when the requested Python version is not the latest patch version. (#1749)
• Improved the error message shown when the requested Python patch version isn't available. (#1749)
• Improved the error message shown if there was a networking or server related error downloading Python. (#1749)
• Adjusted the curl options used when downloading Python to set a maximum download time of 120s to prevent hanging builds in the case of network issues. (#1749)
• Refactored the Python download step to avoid an unnecessary version check HEAD request to S3 prior to downloading Python or reusing a cached install. (#1749)
• Updated the runtime.txt deprecation warning to include a link to the deprecation changelog post. (#1747)
• Improved buildpack metrics for Python version selection. (#1749)
• Improved buildpack metrics for builds that fail. (#1746 and #1749)

v276

• The Python 3.13 version alias now resolves to Python 3.13.2. (#1744)
• The Python 3.12 version alias now resolves to Python 3.12.9. (#1744)
• Deprecated support for the runtime.txt file. (#1743)
• Improved the error messages shown when .python-version, runtime.txt or Pipfile.lock contain an invalid Python version. (#1743)

v275

• Updated Poetry from 1.8.5 to 2.0.1. (#1734)

v274

• Added a deprecation warning for Python 3.9. (#1732)
• Removed support for Python 3.8. (#1732)
• Improved the error messages shown for EOL or unrecognised major Python versions. (#1732)

v273

• Added more Python project related file and directory names to the list recognised by buildpack detection. (#1729)
• Improved the file listing in the error messages shown when buildpack detection fails or when no Python package manager files are found. (#1728)

v272

• Added a warning if the Python buildpack has been run multiple times in the same build. In January 2025 this warning will be made an error. (#1724)
• Added a warning if an existing .heroku/python/ directory is found in the app source. In January 2025 this warning will be made an error. (#1724)
• Improved the error message shown if the buildpack is used on an unsupported stack. (#1724)
• Fixed Dev Center links to reflect recent article URL changes. (#1723)
• Added metrics for the existence of a uv lockfile. (#1725)