- Fixed ``AssertionError`` when ``MACOSX_DEPLOYMENT_TARGET`` was set to ``11``
(PR by Grzegorz Bokota and François-Xavier Coudert)
- Fixed regression introduced in 0.36.0 on Python 2.7 when a custom generator
name was passed as unicode (Scikit-build)
(``TypeError: 'unicode' does not have the buffer interface``)

- Added official Python 3.9 support
- Updated vendored ``packaging`` library to v20.7
- Switched to always using LF as line separator when generating ``WHEEL`` files
(on Windows, CRLF was being used instead)
- The ABI tag is taken from  the sysconfig SOABI value. On PyPy the SOABI value
is ``pypy37-pp73`` which is not compliant with PEP 3149, as it should have
both the API tag and the platform tag. This change future-proofs any change
in PyPy's SOABI tag to make sure only the ABI tag is used by wheel.

- Replaced install dependency on ``packaging`` with a vendored copy of its
``tags`` module
- Fixed ``bdist_wheel`` not working on FreeBSD due to mismatching platform tag
name (it was not being converted to lowercase)

- Switched to the packaging_ library for computing wheel tags
- Fixed a resource leak in ``WheelFile.open()`` (PR by Jon Dufresne)

.. _packaging: https://pypi.org/project/packaging/

- Fixed installation of ``wheel`` from sdist on environments without Unicode
file name support

- Fixed installation of ``wheel`` from sdist which was broken due to a chicken
and egg problem with PEP 517 and setuptools_scm

- Dropped Python 3.4 support
- Added automatic platform tag detection for macOS binary wheels
(PR by Grzegorz Bokota)
- Added the ``--compression=`` option to the ``bdist_wheel`` command
- Fixed PyPy tag generation to work with the updated semantics (328)
- Updated project packaging and testing configuration for :pep:`517`
- Moved the contents of setup.py to setup.cfg
- Fixed duplicate RECORD file when using ``wheel pack`` on Windows
- Fixed bdist_wheel failing at cleanup on Windows with a read-only source tree
- Fixed ``wheel pack`` not respecting the existing build tag in ``WHEEL``
- Switched the project to use the "src" layout
- Switched to setuptools_scm_ for versioning

.. _setuptools_scm: https://github.com/pypa/setuptools_scm/

- Fixed regression from 0.33.5 that broke building binary wheels against the
limited ABI
- Fixed egg2wheel compatibility with the future release of Python 3.10
(PR by Anthony Sottile)

- Don't add the ``m`` ABI flag to wheel names on Python 3.8 (PR by rdb)
- Updated ``MANIFEST.in`` to include many previously omitted files in the sdist

- Reverted PR 289 (adding directory entries to the wheel file) due to
incompatibility with ``distlib.wheel``

- Fixed wheel build failures on some systems due to all attributes being
preserved (PR by Matt Wozniski)

- Fixed empty directories missing from the wheel (PR by Jason R. Coombs)

- Fixed the ``--build-number`` option for ``wheel pack`` not being applied

- Added the ``--build-number`` option to the ``wheel pack`` command
- Fixed bad shebangs sneaking into wheels
- Fixed documentation issue with ``wheel pack`` erroneously being called
``wheel repack``
- Fixed filenames with "bad" characters (like commas) not being quoted in
``RECORD`` (PR by Paul Moore)
- Sort requirements extras to ensure deterministic builds
(PR by PoncinMatthieu)
- Forced ``inplace = False`` when building a C extension for the wheel

- Fixed compatibility with Python 2.7.0 – 2.7.3
- Fixed handling of direct URL requirements with markers (PR by Benoit Pierre)

- Fixed build number appearing in the ``.dist-info`` directory name
- Made wheel file name parsing more permissive
- Fixed wrong Python tag in wheels converted from eggs
(PR by John T. Wodder II)

- Fixed ``AttributeError: 'Requirement' object has no attribute 'url'`` on
setuptools/pkg_resources versions older than 18.8 (PR by Benoit Pierre)
- Fixed ``AttributeError: 'module' object has no attribute
'algorithms_available'`` on Python < 2.7.9 (PR by Benoit Pierre)
- Fixed permissions on the generated ``.dist-info/RECORD`` file

- Removed wheel signing and verifying features
- Removed the "wheel install" and "wheel installscripts" commands
- Added the ``wheel pack`` command
- Allowed multiple license files to be specified using the ``license_files``
option
- Deprecated the ``license_file`` option
- Eliminated duplicate lines from generated requirements in
``.dist-info/METADATA`` (thanks to Wim Glenn for the contribution)
- Fixed handling of direct URL specifiers in requirements
(PR by Benoit Pierre)
- Fixed canonicalization of extras (PR by Benoit Pierre)
- Warn when the deprecated ``[wheel]`` section is used in ``setup.cfg``
(PR by Jon Dufresne)

- Fixed arch as ``None`` when converting eggs to wheels

- Fixed displaying of errors on Python 3
- Fixed single digit versions in wheel files not being properly recognized
- Fixed wrong character encodings being used (instead of UTF-8) to read and
write ``RECORD`` (this sometimes crashed bdist_wheel too)
- Enabled Zip64 support in wheels by default
- Metadata-Version is now 2.1
- Dropped DESCRIPTION.rst and metadata.json from the list of generated files
- Dropped support for the non-standard, undocumented ``provides-extra`` and
``requires-dist`` keywords in setup.cfg metadata
- Deprecated all wheel signing and signature verification commands
- Removed the (already defunct) ``tool`` extras from setup.py

- Added py-limited-api {cp32|cp33|cp34|...} flag to produce cpNN.abi3.{arch}
tags on CPython 3.
- Documented the ``license_file`` metadata key
- Improved Python, abi tagging for ``wheel convert``. Thanks Ales Erjavec.
- Fixed ``>`` being prepended to lines starting with "From" in the long
description
- Added support for specifying a build number (as per PEP 427).
Thanks Ian Cordasco.
- Made the order of files in generated ZIP files deterministic.
Thanks Matthias Bach.
- Made the order of requirements in metadata deterministic. Thanks Chris Lamb.
- Fixed ``wheel install`` clobbering existing files
- Improved the error message when trying to verify an unsigned wheel file
- Removed support for Python 2.6, 3.2 and 3.3.