CHANGELOG.md

Changelog

Unreleased

v275 - 2025-01-13

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

v274 - 2025-01-08

• 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 - 2025-01-03

• 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 - 2024-12-13

• 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)

v271 - 2024-12-12

• Updated the Python 3.8 EOL warning message with the new sunset date. (#1721)
• Improved the error message shown when pip install fails due to pip rejecting a package with invalid version metadata. (#1718)
• Improved the error message shown when the copy of pip bundled in the ensurepip module cannot be found. (#1720)

v270 - 2024-12-10

• Changed the default Python version for new apps from 3.12 to 3.13. (#1715)
• Changed Python version pinning behaviour for apps that do not specify a Python version. Repeat builds are now pinned to the major Python version only (3.X) instead of the full Python version (3.X.Y), so that they always use the latest patch version. (#1714)
• Updated Poetry from 1.8.4 to 1.8.5. (#1716)

v269 - 2024-12-04

• The Python 3.13 version alias now resolves to Python 3.13.1. (#1712)
• The Python 3.12 version alias now resolves to Python 3.12.8. (#1712)
• The Python 3.11 version alias now resolves to Python 3.11.11. (#1712)
• The Python 3.10 version alias now resolves to Python 3.10.16. (#1712)
• The Python 3.9 version alias now resolves to Python 3.9.21. (#1712)

v268 - 2024-12-04

• Updated pip from 24.0 to 24.3.1. (#1685)
• Updated wheel from 0.44.0 to 0.45.1. (#1707)

v267 - 2024-11-12

• Deprecated using Pipenv without a lockfile (Pipfile.lock). (#1695)
• Fixed Poetry venv creation when using an outdated Python version whose ensurepip module doesn't enable isolated mode, and the app's build directory contents shadows a package imported by pip (such as brotli). (#1698)

v266 - 2024-11-08

• Added a warning when the files for multiple package managers are found. In the future this warning will become an error. (#1692)
• Updated the build log message shown when installing dependencies to include the package manager command being run. (#1689)
• Changed test dependency installation on Heroku CI to now install requirements.txt and requirements-test.txt in a single pip install invocation rather than separately. This allows pip's resolver to resolve any version conflicts between the two files. (#1689)
• Improved the error messages and buildpack metrics for package manager related failures. (#1689)
• Improved the build log output, error messages and buildpack failure metrics for the NLTK downloader feature. (#1690)

v265 - 2024-11-06

• Fixed Poetry installation when using outdated patch versions of Python 3.8, 3.9 and 3.10, whose bundled pip doesn't support the --python option. (#1687)

v264 - 2024-11-06

• Added support for the package manager Poetry. Apps must have a pyproject.toml + poetry.lock and no other package manager files (otherwise pip/Pipenv will take precedence for backwards compatibility). (#1682)

v263 - 2024-10-31

• Fixed cache handling so that it now also discards the cache when the package manager (or its version) changes. (#1679)
• Improved the build log output shown when restoring or discarding the cache. For example, if the cache was invalidated all reasons are now shown. (#1679)
• Stopped performing unnecessary cache file copies when the cache is due to be invalidated. This required moving the cache restoration step to after the bin/pre_compile hook runs. (#1679)
• Fixed cache restoration in the case where an app's requirements.txt was formerly a symlink. (#1679)
• Added buildpack metrics for the status of the cache and duration of cache restoration/saving. (#1679)

v262 - 2024-10-25

• Updated buildpack-generated warning messages to use colour and be more consistently formatted. (#1666)
• Improved build log output and error messages for the bin/pre_compile and bin/post_compile customisation hooks. (#1667)

v261 - 2024-10-14

• Added support for configuring the Python version using a .python-version file. Both the 3.N and 3.N.N version forms are supported (the former is recommended). The existing runtime.txt file will take precedence if both files are found, however, we recommend switching to .python-version since it is more commonly supported in the Python ecosystem. (#1664)
• Added support for specifying only the Python major version in runtime.txt instead of requiring the full Python version (for example python-3.N instead of python-3.N.N). (#1664)

v260 - 2024-10-10

• Added support for Python 3.13. (#1661)
• Removed the idle3 and pydoc3 scripts since they do not work with relocated Python and so have been broken for some time. Invoke them via their modules instead (e.g. python -m pydoc). (#1661)

v259 - 2024-10-09

• Improved build log output about the detected Python version. (#1658)
• Improved error messages shown when the requested Python version is not a valid version string or is for an unknown/non-existent major Python version. (#1658)
• Improved error messages shown when Pipfile.lock is not valid JSON. (#1658)
• Fixed invalid Python versions being silently ignored when they were specified via the python_version field in Pipfile.lock. (#1658)
• Added support for Python 3.9 on Heroku-24. (#1656)
• Added buildpack metrics for use of outdated Python patch versions and occurrences of internal errors. (#1657)
• Improved the robustness of buildpack error handling by enabling inherit_errexit. (#1655)

v258 - 2024-10-01

• Added support for Python 3.12.7. (#1650)
• Changed the default Python version for new apps from 3.12.6 to 3.12.7. (#1650)
• Fixed Django collectstatic debug output being shown if DEBUG_COLLECTSTATIC was set to 0 or the empty string. (#1646)
• Stopped adding a trailing : to C_INCLUDE_PATH, CPLUS_INCLUDE_PATH, LIBRARY_PATH, LD_LIBRARY_PATH and PKG_CONFIG_PATH. (#1645)
• Removed remnants of the unused .heroku/vendor/ directory. (#1644)

v257 - 2024-09-24

• Moved the SQLite3 install step prior to installing dependencies when using Pipenv. This now matches the behaviour when using pip and allows dependencies to actually use the headers. (#1640)
• Stopped exposing the SKIP_PIP_INSTALL env var to bin/post_compile and other subprocesses when using Pipenv. (#1640)
• Stopped creating .heroku/python/requirements-{declared,installed}.txt files when using pip. (#1640)
• Stopped creating a placeholder requirements.txt file when an app only has a setup.py file and no other package manager files. Instead pip is now invoked directly using --editable .. (#1640)
• Improved buildpack metrics for package manager detection and duration of install steps. (#1640)
• Updated buildpack-generated error messages to use colour and be more consistently formatted. (#1639)

v256 - 2024-09-07

• Added support for Python 3.8.20, 3.9.20, 3.10.15, 3.11.10 and 3.12.6. (#1632)
• Changed the default Python version for new apps from 3.12.5 to 3.12.6. (#1632)
• Updated wheel from 0.43.0 to 0.44.0. (#1629)

v255 - 2024-08-07

• Added support for Python 3.12.5. (#1622)
• Changed the default Python version for new apps from 3.12.4 to 3.12.5. (#1622)

v254 - 2024-07-16

• Updated setuptools from 69.2.0 to 70.3.0. (#1614)
• Updated pipenv from 2023.12.1 to 2024.0.1. (#1601)

v253 - 2024-07-01

• Improved the error messages shown when an app is missing the necessary Python package manager files. (#1608)

v252 - 2024-06-17

• Removed export of Pipfile.lock to requirements.txt during the build. (#1593)
• Removed internal pipenv-to-pip script that was unintentionally exposed onto PATH. (#1593)
• Stopped exposing the internal BIN_DIR, BPLOG_PREFIX, EXPORT_PATH and PROFILE_PATH environment variables to bin/{pre,post}_compile and other subprocesses. (#1595 and #1597)
• Implemented the bin/report build report API and removed log based metrics. (#1597)

v251 - 2024-06-07

• Added support for Python 3.12.4. (#1591)
• Changed the default Python version for new apps from 3.12.3 to 3.12.4. (#1591)

v250 - 2024-04-26

• Added support for Heroku-24. (#1575)

v249 - 2024-04-18

• Improved the error message shown for EOL Python versions when using a stack for which those versions were never built. (#1570)
• Fixed the "Python security update is available" warning being shown when the requested version is newer than the latest version known to the buildpack. (#1569)
• Fixed glibc warnings seen when downgrading the stack version. (#1568)
• Changed compression format and S3 URL for Python runtime archives. (#1567)
• Adjusted compiler options used to build Python for improved parity with the Docker Hub Python images. (#1566)
• Excluded LD_LIBRARY_PATH and PYTHONHOME app config vars when invoking subprocesses during the build. (#1565)

v248 - 2024-04-09

• Added support for Python 3.12.3. (#1560)
• Changed the default Python version for new apps from 3.12.2 to 3.12.3. (#1560)

v247 - 2024-04-08

• Added support for Python 3.11.9. (#1558)

v246 - 2024-03-25

• Updated pip from 23.3.2 to 24.0. (#1541)
• Updated setuptools from 68.2.2 to 69.2.0. (#1553)
• Updated wheel from 0.42.0 to 0.43.0. (#1550)
• Updated pipenv from 2023.11.15 to 2023.12.1. (#1540)

v245 - 2024-03-21

• Added support for Python 3.8.19, 3.9.19 and 3.10.14. (#1551)

v244 - 2024-03-13

• Improved the automatic WEB_CONCURRENCY feature: (#1547)
  • Switched to a dynamic calculation based on dyno CPU cores and memory instead of a hardcoded mapping.
  • Decreased default concurrency on performance-m / private-m / shield-m dynos from 8 to 5.
  • Increased default concurrency on performance-l / private-l / shield-l dynos from 11 to 17.
  • Added logging of memory/CPU/concurrency information to the app logs (for web dynos only).

v243 - 2024-02-07

• Added support for Python 3.11.8 and 3.12.2. (#1538).
• Changed the default Python version for new apps from 3.12.1 to 3.12.2. (#1538)

v242 - 2024-01-11

• Updated pip from 23.3.1 to 23.3.2. (#1524)
• Fixed repeat/cached Pipenv builds of local file = dependencies. (#1526)
• Fixed the caching of editable VCS Pipenv dependency repositories. (#1528)

v241 - 2023-12-08

• Changed the default Python version for new apps from Python 3.11 to Python 3.12. (#1516).
• Added support for Python 3.11.7 and 3.12.1. (#1517 and #1518).
• Added a deprecation warning for Python 3.8. (#1515)

v240 - 2023-11-30

• Updated setuptools from 68.0.0 to 68.2.2. (#1501)
• Updated wheel from 0.41.3 to 0.42.0. (#1511)
• Updated pipenv from 2023.7.23 to 2023.11.15. (#1502 and #1512)

v239 - 2023-11-08

• Dropped support for Python 3.7. (#1508)

v238 - 2023-11-06

• Updated pip from 23.2.1 to 23.3.1. (#1496)
• Updated wheel from 0.41.0 to 0.41.3. (#1482 and #1503)

v237 - 2023-10-03

• Fixed pkgutil.find_loader deprecation warning when using Python 3.12. (#1493)

v236 - 2023-10-02

• Added support for Python 3.12. (#1490)
• Added support for Python 3.11.6. (#1491)
• Changed the default Python version for new apps from 3.11.5 to 3.11.6. (#1491)

v235 - 2023-08-25

• Added support for Python 3.8.18, 3.9.18, 3.10.13 and 3.11.5. (#1477)
• Changed the default Python version for new apps from 3.11.4 to 3.11.5. (#1477)

v234 - 2023-07-24

• Updated pip from 23.1.2 to 23.2.1. (#1465 and #1470)
• Updated setuptools from 67.8.0 to 68.0.0. (#1467)
• Updated wheel from 0.40.0 to 0.41.0. (#1469)
• Updated pipenv from 2023.2.4 to 2023.7.23. (#1468 and #1471)
• Updated the Python 3.7 deprecation message to reflect that it has now reached end-of-life. (#1460)

v233 - 2023-06-07

• Python 3.7.17, 3.8.17, 3.9.17, 3.10.12 and 3.11.4 are now available (#1454).
• The default Python version for new apps is now 3.11.4 (previously 3.11.3) (#1454).
• Updated setuptools from 67.7.2 to 67.8.0. (#1456)
• Removed support for Heroku-18. (#1449)

v232 - 2023-04-27

• Updated pip from 23.0.1 to 23.1.2. (#1441)
• Updated setuptools from 67.6.1 to 67.7.2. (#1441)
• The pip bootstrap step is now performed using the pip wheel bundled with the Python stdlib, rather than one downloaded from S3. (#1442 and #1444)

v231 - 2023-04-12

• Updated setuptools from 63.4.3 to 67.6.1. (#1437)
• Updated wheel from 0.38.4 to 0.40.0. (#1437)
• Raised curl connection timeout threshold from 5 to 10 seconds. (#1439)

v230 - 2023-04-06

• Python 3.10.11 and 3.11.3 are now available (#1433).
• The default Python version for new apps is now 3.11.3 (previously 3.11.2) (#1433).

v229 - 2023-03-10

• Downgrade pipenv from 2023.2.18 to 2023.2.4 (#1425).

v228 - 2023-02-21

• Drop support for Python 3.6 (#1415).

v227 - 2023-02-20

• Update pip from 22.3.1 to 23.0.1 for Python 3.7+ (#1413).
• Update pipenv from 2023.2.4 to 2023.2.18 for Python 3.7+ (#1412).

v226 - 2023-02-14

• Use Python 3.11 as the default Python version for new apps (previously Python 3.10) (#1408).
• Update wheel from 0.37.1 to 0.38.4 for Python 3.7+ (#1409).

v225 - 2023-02-08

• Python 3.10.10 and 3.11.2 are now available (#1405).
• The default Python version for new apps is now 3.10.10 (previously 3.10.9) (#1405).
• Update Pipenv from 2020.11.15 to: (#1407)
  • 2022.4.8 for Python 3.6
  • 2023.2.4 for Python 3.7+
• Add a deprecation warning for Python 3.7 (#1404).

v224 - 2022-12-07

• Python 3.7.16, 3.8.16, 3.9.16, 3.10.9 and 3.11.1 are now available (#1392).
• The default Python version for new apps is now 3.10.9 (previously 3.10.8) (#1392).

v223 - 2022-11-07

• Update pip from 22.2.2 to 22.3.1 for Python 3.7+ (#1387).

v222 - 2022-10-25

• Add support for Python 3.11 (#1379).

v221 - 2022-10-12

• Python 3.7.15, 3.8.15, 3.9.15 and 3.10.8 are now available (#1376).
• The default Python version for new apps is now 3.10.8 (previously 3.10.7) (#1376).
• Fix automatic provisioning of Postgres DB addons (#1375).

v220 - 2022-09-28

• Improve the wording of the Python 2.7 EOL error message (#1367).

v219 - 2022-09-26

• Drop support for Python 2.7, 3.4 and 3.5 (#1364).
• Drop support for PyPy (#1364).
• The Heroku Postgres database auto-provisioning feature now provisions a DB in fewer cases (#1363).

v218 - 2022-09-07

• Python 3.7.14, 3.8.14 and 3.9.14 are now available (#1362).

v217 - 2022-09-06

• Python 3.10.7 is now available (#1361).
• The default Python version for new apps is now 3.10.7 (previously 3.10.6) (#1361).

v216 - 2022-08-17

• Ensure path rewriting works when using setuptools v64's new PEP660-based editable install mode (#1357).
• Display an EOL warning for Python 3.4, 3.5 and 3.6 (#1356).
• Improve the EOL warning for Python 2.7 (#1356).
• Display a deprecation warning for PyPy support (#1356).

v215 - 2022-08-15

• Update pip from 22.1.2 to 22.2.2 for Python 3.7+ (#1344).
• Update setuptools from 60.10.0 to 63.4.3 for Python 3.7+ (#1344).
• Prevent stray cp: cannot stat ... error message in build log output when using Pipenv (#1350).
• Remove BUILD_WITH_GEO_LIBRARIES sunset messaging (#1347).
• Remove outdated Django version warning (#1345).
• Remove redundant package install warning checks (#1348).

v214 - 2022-08-02

• Python 3.10.6 is now available (#1342).
• The default Python version for new apps is now 3.10.6 (previously 3.10.5) (#1342).

v213 - 2022-06-14

• Enable retries and connection timeouts when using curl (#1335).
• Correct the error message shown when downloading a valid Python version fails (#1335).
• Switch to the recommended regional S3 domain instead of the global one (#1334).

v212 - 2022-06-07

• Python 3.10.5 is now available (#1332).
• The default Python version for new apps is now 3.10.5 (previously 3.10.4) (#1332).
• Update pip from 22.0.4 to 22.1.2 for Python 3.7+ (#1331).
• Add support for Heroku-22 (#1299).

v211 - 2022-05-17

• Python 3.9.13 is now available (#1326).
• Use shared builds + LTO when building Python 3.10 binaries (#1320). Note: This and the other Python binary changes below will only take effect for future Python version releases (or future Heroku stacks) - existing Python binaries are not being recompiled.
• Strip debugging symbols from the Python binary and libraries (#1321).
• Switch the pre-generated .pyc files for the Python stdlib from timestamp to unchecked-hash validation mode, for improved compatibility with Cloud Native Buildpacks (#1322).
• Stop shipping optimisation level one and two .pyc files with the Python stdlib (#1322).
• Use the expat package from the stack image rather than CPython's vendored version, when building Python binaries (#1319).

v210 - 2022-04-14

• Fix typo in the BUILD_WITH_GEO_LIBRARIES end-of-life error message (#1307).
• No longer set a fallback value for $STACK, since it is always set on Heroku (#1308).
• Adjust the configure options and packaging process for Python 3.7 releases, to enable loadable extensions in the _sqlite module, and to remove the idle_test module (#1309). This change will only take effect as of the next Python 3.7 release (3.7.14).
• Update pip from 21.3.1 to 22.0.4 for Python 3.7+ (#1310)
• Update setuptools from 57.5.0 to: (#1310)
  • 59.6.0 for Python 3.6
  • 60.10.0 for Python 3.7+
• Update wheel from 0.37.0 to 0.37.1 for Python 2.7 and Python 3.5+ (#1310)

v209 - 2022-03-24

• Python 3.9.12 and 3.10.4 are now available (CPython) (#1300).
• The default Python version for new apps is now 3.10.4 (previously 3.10.3) (#1300).

v208 - 2022-03-23

• Use Python 3.10 as the default Python version for new apps (previously Python 3.9) (#1296).

v207 - 2022-03-16

• Python 3.7.13, 3.8.13, 3.9.11 and 3.10.3 are now available (CPython) (#1293).
• The default Python version for new apps is now 3.9.11 (previously 3.9.10) (#1293).
• Adjust the configure options and packaging process for Python 3.8 releases to enable PGO, enable loadable extensions in the _sqlite module, and to remove the idle_test module (#1293). Python 3.8 releases on Heroku prior to 3.8.13 are not affected.

v206 - 2022-01-14

• Python 3.9.10 and 3.10.2 are now available (CPython) (#1281).
• The default Python version for new apps is now 3.9.10 (previously 3.9.9) (#1281).

v205 - 2021-12-06

• Python 3.10.1 is now available (#1271).

v204 - 2021-11-16

• Python 3.9.9 is now available (#1268).
• The default Python version for new apps is now 3.9.9 (previously 3.9.8) (#1268).

v203 - 2021-11-08

• Python 3.9.8 is now available (#1263).
• The default Python version for new apps is now 3.9.8 (previously 3.9.7) (#1263).
• Adjust the configure options and packaging process for Python 3.9 releases to enable PGO, enable loadable extensions in the _sqlite module, and to remove the idle_test module (#1263). Python 3.9 releases on Heroku prior to 3.9.8 are not affected.

v202 - 2021-11-01

• Update pip from 20.2.4 to: (#1259)
  • 20.3.4 for Python 2.7 and 3.5
  • 21.3.1 for Python 3.6+

v201 - 2021-10-20

• Update setuptools from 47.1.1 to: (#1254)
  • 50.3.2 for Python 3.5
  • 57.5.0 for Python 3.6+
• Update wheel from 0.36.2 to 0.37.0 for Python 2.7 and Python 3.5+ (#1254).
• Perform editable package .pth and .egg-link path rewriting at runtime (#1252).

v200 - 2021-10-04

• Add support for Python 3.10 (#1246).
• Adjust the configure options and packaging process for Python 3.10 to enable PGO, enable loadable extensions in the _sqlite module, and to remove the idle_test module (#1246).

v199 - 2021-09-05

• Python 3.6.15 and 3.7.12 are now available (CPython) (#1238).

v198 - 2021-08-30

• Python 3.8.12 and 3.9.7 are now available (CPython) (#1236).
• The default Python version for new apps is now 3.9.7 (previously 3.9.6) (#1236).

v197 - 2021-06-28

• Python 3.6.14, 3.7.11, 3.8.11 and 3.9.6 are now available (CPython) (#1219).
• The default Python version for new apps is now 3.9.6 (previously 3.9.5) (#1219).
• Remove testing & binary generation support for Heroku-16 (#1214).

v196 - 2021-05-25

• Django collectstatic is no longer skipped if DISABLE_COLLECTSTATIC is set to 0 or the empty string (#1208).
• If Django collectstatic is skipped, output the reason why (#1208).
• Output a deprecation warning when collectstatic is skipped via the .heroku/collectstatic_disabled file (#1208).
• Remove redundant "Cedar-14 is unsupported" error (#1212).

v195 - 2021-05-03

• Python 3.8.10 and 3.9.5 are now available (CPython) (#1204).

v194 - 2021-04-26

• Always output the Python version used and reason why (#1196).

v193 - 2021-04-13

• Update pip from 20.1.1 to 20.2.4 for Python 2.7 and Python 3.5+ (#1192).
• Update wheel from 0.34.2 to 0.36.2 for Python 2.7 and Python 3.5+ (#1191).
• Support build environments where $BUILD_DIR is set to a symlink of /app (#992).

v192 - 2021-04-06

• Python 3.8.9 and 3.9.4 are now available (CPython) (#1188).
• Use Python 3.9 as the default Python version for new apps (previously Python 3.6) (#1187).
• Remove Airflow SLUGIFY_USES_TEXT_UNIDECODE workaround (#1186).
• Fix grammar in the Python 2 EOL message (#1182).

v191 - 2021-02-19

• Python 3.8.8 and 3.9.2 are now available (CPython) (#1178).

v190 - 2021-02-16

• Python 3.6.13 and 3.7.10 are now available (CPython) (#1174).
• The default Python version for new apps is now 3.6.13 (previously 3.6.12) (#1174).

v189 - 2021-02-12

• Update pipenv from 2018.5.18 to 2020.11.15 (#1169).
• Remove pinning of pip to 9.0.2 when using pipenv (#1169).

v188 - 2020-12-21

• Python 3.8.7 is now available (CPython) (#1125).

v187 - 2020-12-08

• Python 3.9.1 is now available (CPython) (#1127).

v186 - 2020-11-18

• Update the BUILD_WITH_GEO_LIBRARIES error message (#1121).
• Switch NLTK feature detection away from sp-grep (#1119).
• Switch Django collectstatic feature detection away from sp-grep (#1119).
• Remove vendored sp-grep script (#1119).
• Remove vendored pip-diff script (#1118).
• Remove vendored pip-grep script (#1116).

v185 - 2020-11-12

• Error if the unsupported BUILD_WITH_GEO_LIBRARIES env var is set (#1115).
• Remove deprecated GDAL/GEOS/PROJ support (#1113).
• Remove vendored jq binary (#1112).
• Remove redundant Mercurial install step (#1111).
• Remove support for the Cedar-14 stack (#1110).

v184 - 2020-10-21

• Vendor buildpack-stdlib instead of fetching from S3 (#1100).
• Fix metric names for metrics emitted within sub_env (#1099).

v183 - 2020-10-12

• Add support for Heroku-20 (#968).

v182 - 2020-10-06

• Python 3.9.0 is now available (CPython) (#1090).
• Migrate from the lang-python S3 bucket to heroku-buildpack-python (#1089).
• Remove vendor/shunit2 (#1086).
• Replace BUILDPACK_VENDOR_URL and USE_STAGING_BINARIES with BUILDPACK_S3_BASE_URL (#1085).

v181 - 2020-09-29

• PyPy 2.7 and 3.6, version 7.3.2 are now available (Note: PyPy support is in beta) (#1081).

v180 - 2020-09-24

• Python 3.8.6 is now available (CPython) (#1072).

v179 - 2020-09-23

• Remove duplicate pipenv metric event (#1070).
• Emit metrics for how the Python version was chosen for an app (#1069).
• Emit Python version metric events for all builds, not just clean installs (#1066).

v178 - 2020-09-07

• Python 3.5.10 is now available (CPython) (#1062).

v177 - 2020-08-18

• Python 3.6.12 and 3.7.9 are now available (CPython) (#1054).
• The default Python version for new apps is now 3.6.12 (previously 3.6.11) (#1054).

v176 - 2020-08-12

• Rebuild the Python 3.4.10 archives with the correct version of Python (#1048).
• Fix the security update version check message for apps using PyPy (#1040).
• Remove vendor/test-utils (#1043).

v175 - 2020-08-05

• Update pip from 20.0.2 to 20.1.1 for Python 2.7 and Python 3.5+ (#1030).
• Update setuptools from 39.0.1 to: (#1024)
  • 44.1.1 for Python 2.7
  • 43.0.0 for Python 3.4
  • 47.1.1 for Python 3.5+
• Switch the heroku-buildpack-python repository default branch from master to main (#1029).

v174 - 2020-07-30

• For repeat builds, also manage the installed versions of setuptools/wheel, rather than just that of pip (#1007).
• Install an explicit version of wheel rather than the latest release at the time (#1007).
• Output the installed version of pip, setuptools and wheel in the build log (#1007).
• Errors installing pip/setuptools/wheel are now displayed in the build output and fail the build early (#1007).
• Install pip using itself rather than get-pip.py (#1007).
• Disable pip's version check + cache when installing pip/setuptools/wheel (#1007).
• Install setuptools from PyPI rather than a vendored copy (#1007).
• Reduce the number of environment variables exposed to bin/{pre,post}_compile and other subprocesses (#1011).

v173 - 2020-07-21

• Python 3.8.5 is now available (CPython).

v172 - 2020-07-17

• Python 3.8.4 is now available (CPython).

v171 - 2020-07-07

• Python 3.6.11 and 3.7.8 are now available (CPython).

v170 - 2020-05-19

• Python 2.7.18, 3.5.9, 3.7.7 and 3.8.3 are now available (CPython).
• PyPy 2.7 and 3.6, version 7.3.1 are now available (Note: PyPy support is in beta).
• Docs: Fix explanation of runtime.txt generation when using pipenv.
• Bugfix: Correctly detect Python version when using a python_version of 3.8 in Pipfile.lock.

v169 - 2020-04-22

• Add a Hatchet test for python 3.8.2
• Set Code Owners to @heroku/languages
• Bugfix: Caching on subsequent redeploys
• Update tests to support latest version of Python

v168 - 2020-04-06

• Doc: Update Readme with version numbers
• update Code Owners to include the Heroku Buildpack Maintainers team
• Deprecation warning: BUILD_WITH_GEO_LIBRARIES is now deprecated. See warning for details.
• Clean up build log output
• Update Python versions in README to match docs
• Django version detection fixed, link updated

v167 - 2020-03-26

• Add failcase for cache busting
• Bugfix: Clearing pip dependencies

v166 - 2020-03-05

• Correct ftp to https in vendored file
• Warn for Django 1.11 approaching EOL, provide link to roadmap

v165 - 2020-02-27

• Python 3.8.2 now available.

v164 - 2020-02-20

• Update requirements.txt builds to use pip 20.0.2
• Download get-pip.py to tmpdir instead of root dir

v163 - 2019-12-23

• New pythons released: Python 3.8.1, 3.7.6, 3.6.10 (CPython) Beta Release: Pypy 2.7 and 3.6, version 7.2.0

v162 - 2019-12-06

• Bug fix: fragile sqlite3 install

v161 - 2019-12-02

• Bug fix: Sqlite3 version bump

v160 - 2019-10-23

• Bugfix: Pipenv no longer installs twice in CI

v159 - 2019-10-22

• Python 2.7.17 now available on Heroku 18 and 16.

v158 - 2019-10-21

• Python 3.7.5 and 3.8.0 now available on Heroku 18 and 16.
• Add support for Python 3.8 branch
• Sqlite3 Update:
  • Test Improvements
• Add support for staging binary testing

v157 - 2019-09-18

• Typo fixes

v156 - 2019-09-12

• Python 3.6.9 and 3.7.4 now available.

• Move get-pip utility to S3

• Build utility and documentation updates

• Bump Hatchet tests to point at new default python version.

v155 - 2019-08-22

add docs and make target for heroku-18 bob builds

v154 - 2019-07-17

Fix python 3.5.7 formula actually building 3.7.2

v153 - 2019-06-21

Hotfix for broken heroku-16 deploys

v152 - 2019-04-04

Python 3.7.3 now available.

v151 - 2019-03-21

Python 3.5.7 and 3.4.10 now available on all Heroku stacks.

v150 - 2019-03-13

Python 2.7.16 now available on all Heroku stacks.

v149 - 2019-03-04

Hotfix for broken Cedar 14 deploys

v148 - 2019-02-21

No user facing changes, improving internal metrics

v147 - 2019-02-07

Python 3.7.2 and 3.6.8 now available on all Heroku stacks.

v146 - 2018-11-11

Python 3.7.1, 3.6.7, 3.5.6 and 3.4.9 now available on all Heroku stacks.

v145 - 2018-11-08

Testing and tooling expanded to better support new runtimes

v144 - 2018-10-10

Switch to cautious upgrade for Pipenv install to ensure the pinned pip version is used with Pipenv

v143 - 2018-10-09

Add support for detecting SLUGIFY_USES_TEXT_UNIDECODE, which is required to install Apache Airflow version 1.10 or higher.

v142 - 2018-10-08

Improvements to Python install messaging

v139, 140, 141

No user-facing changes, documenting for version clarity

v138 - 2018-08-01

Use stack image SQLite3 instead of vendoring

v137 - 2018-07-17

Prevent 3.7.0 from appearing as unsupported in buildpack messaging.

v136 - 2018-06-28

Upgrade to 3.6.6 and support 3.7.0 on all runtimes.

v135 - 2018-05-29

Upgrade Pipenv to v2018.5.18.

v134 - 2018-05-02

Default to 3.6.5, bugfixes.

v133

Fixes for pip 10 release.

v132

Improve pip installation, with the release of v9.0.2.

v131

Fix bug with pip.

v130

Better upgrade strategy for pip.

v129

Don't upgrade pip (from v128).

v128

Upgrade pip, pin to Pipenv v11.8.2.

v127

Pin to Pipenv v11.7.1.

v126

Bugfixes.

v125

Bugfixes.

v124

Update buildpack to automatically install [dev-packages] during Heroku CI Pipenv builds.

• Skip installs if Pipfile.lock hasn't changed, and uninstall stale dependencies with Pipenv.
• Set PYTHONPATH during collectstatic runs.
• No longer warn if there is no Procfile.
• Update Pipenv's "3.6" runtime specifier to point to "3.6.4".

v123

Update gunicorn init.d script to allow overrides.

v122

Update default Python to v3.6.4.

v121

Update default Python to v3.6.3.

v120

Use $ pipenv --deploy.

v119

Improvements to Pipenv support, warning on unsupported Python versions.

• We now warn when a user is not using latest 2.x or 3.x Python.
• Heroku now supports [requires] python_full_version in addition to python_version.

v118

Improvements to Pipenv support.

v117

Bug fix.

v116

Vendoring improvements.

• Geos libraries should work on Heroku-16 now.
• The libffi/libmemcached vendoring step is now skipped on Heroku-16 (since they are installed in the base image).

v115

Revert a pull request.

• No longer using sub_env for pip install step.

v114

• Bugfixes.

Blacklisting PYTHONHOME and PYTHONPATH for older apps. Upgrades to nltk support.

v113

Updates to Pipenv support.

v112

Bugfix.

• Fixed grep output bug.

v111

Linting, bugfixes.

v110

Update default Python to 3.6.2.

v109

Update Default Python to 3.6.1, bugfixes.

• Fixed automatic pip uninstall of dependencies removed from requirements.txt.

v108

Fix output for collectstatic step.

v107

Bugfix for C dependency installation.

v106

Don't install packages that could mess up packaging.

• The Python buildpack will automatically remove six, pyparsing, appdirs, setuptools, and distribute from a requirements.txt file now, as these packages are provided by the Python buildpack.

v105

Improvements to output messaging.

v104

General improvements.

• Fix for Heroku CI.
• Use pkg_resources to check if a distribution is installed instead of parsing requirements.txt. (#395)

v103

Bug fixes and improvements.

• Fix for Pipenv.
• Fix for Heroku CI.
• Improve handling of WEB_CONCURRENCY when using multiple buildpacks.
• Adjust environment variables set during the build to more closely match those in the dyno environment (DYNO is now available, STACK is not).
• Restore the build cache prior to running bin/pre_compile.

v102

Buildpack code cleanup.

• Improved messaging around NLTK.

v101

Updated setuptools installation method.

• Improved pipenv support.

v100

Preliminary pipenv support.

v99

Cleanup.

v98

Official NLTK support and other improvements.

• Support for nltk.txt file for declaring corpora to be downloaded.
• Leading zeros for auto-set WEB_CONCURRENCY.

v97

Improved egg-link functionality.

v96

Bugfix.

v95

Improved output support.

v94

Improved support for PyPy.

v93

Improved support for PyPy.

v92

Improved cache functionality and fix egg-links regression.

v91

Bugfix, rolled back to v88.

v90

Bugfix.

v89

Improved cache functionality and fix egg-links regression.

v88

Fixed bug with editable pip installations.

v87

Updated default Python 2.7.13.

• Python 2.7.13 uses UCS-4 build, more compatible with linux wheels.
• Updated setuptools to v32.1.0.

v86

Refactor and multi-buildpack compatibility.

v85

Packaging fix.

v84

Updated pip and setuptools.

• Updated pip to v9.0.1.
• Updated setuptools to v28.8.0.

v83

Support for Heroku CI.

• Cffi support for argon2

v82 - 2016-08-22

Update to library detection mechanisms (pip-pop).

• Updated setuptools to v25.5.0

v81 - 2016-06-28

Updated default Python to 2.7.11.

• Updated pip to v8.1.2.
• Updated setuptools to v23.1.0.

v80 - 2016-04-05

Improved pip-pop compatibility with latest pip releases.

v79 - 2016-03-22

Compatibility improvements with heroku-apt-buildpack.

v78 - 2016-03-18

Added automatic configuration of Gunicorn's FORWARDED_ALLOW_IPS setting.

Improved detection of libffi dependency when using bcrypt via Django[bcrypt].

Improved GDAL support.

• GDAL dependency detection now checks for pygdal and is case-insensitive.
• The vendored GDAL library has been updated to 1.11.1.
• GDAL bootstrapping now also installs the GEOS and Proj.4 libraries.

Updated pip to 8.1.1 and setuptools to 20.3.

v77 - 2016-02-10

Improvements to warnings and minor bugfix.

v76 - 2016-02-08

Improved Django collectstatic support.

• $ python manage.py collectstatic will only be run if Django is present in requirements.txt.
• If collectstatic fails, the build fails. Full traceback is provided.
• $DISABLE_COLLECTSTATIC: skip collectstatic step completely (not new).
• $DEBUG_COLLECTSTATIC: echo environment variables upon collectstatic failure.
• Updated build output style.
• New warning for outdated Python (via pip InsecurePlatform warning).

v75 - 2016-01-29

Updated pip and Setuptools.

v74 - 2015-12-29

Added warnings for lack of Procfile.

v72 - 2015-12-07

Updated default Python to 2.7.11.

v72 - 2015-12-03

Added friendly warnings for common build failures.

v70 - 2015-10-29

Improved compatibility with multi and node.js buildpacks.

v69 - 2015-10-12

Revert to v66.

v68 - 2015-10-12

Fixed .heroku/venv error with modern apps.

v67 - 2015-10-12

Further improved cache compatibility with multi and node.js buildpacks.

v66 - 2015-10-09

Improved compatibility with multi and node.js buildpacks.

v65 - 2015-10-08

Reverted v64.

v64 - 2015-10-08

Improved compatibility with multi and node.js buildpacks.

v63 - 2015-10-08

Updated pip and Setuptools.

• Setuptools updated to v18.3.2
• pip updated to v7.1.2

v62 - 2015-08-07

Updated pip and Setuptools.

• Setuptools updated to v18.1
• pip updated to v7.1.0

v61 - 2015-06-30

Updated pip and Setuptools.

• Setuptools updated to v18.0.1
• pip updated to v7.0.3

v60 - 2015-05-27

Default Python is now latest 2.7.10. Updated pip and Distribute.

• Default Python version is v2.7.10
• Setuptools updated to v16.0
• pip updated to v7.0.1