• Python 3.14 is supported.
• Python 3.8 and 3.9 are no longer supported.
• Fix an issue where flushing using igzip_threaded caused a gzip end of stream
  and started a new gzip stream. In essence creating a concatenated gzip
  stream. Now it is in concordance with how single threaded gzip streams
  are flushed using Z_SYNC_FLUSH.
• Change build backend to setuptools-scm which is more commonly used and
  supported.
• Include test packages in the source distribution, so source distribution
  installations can be verified.
• Fix an issue where some tests failed because they ignored PYTHONPATH.
• Enable support for free-threading and build free-threaded wheels for
  CPython 3.14. Thanks to@lysnikolaou and@ngoldbaum.

Contributors

• Use upstream ISA-L version 2.31.1 which includes patches to make
  installation on MacOS ARM64 possible.
• Fix a bug where bytes were copied in the wrong order on big endian
  architectures. Fixes test failures on s390x.
• Enable building on GNU/Hurd platforms.

• Fix a bug where flushing files when writing in threaded mode did not work
  properly.
• Prevent threaded opening from blocking python exit when an error is thrown
  in the calling thread.

• Include a patched ISA-L version 2.31. The applied patches make compilation
  and wheelbuilding on MacOS ARM64 possible.
• Fix a bug where READ and WRITE in isal.igzip were inconsistent with the
  values in gzip on Python 3.13
• Small simplifications to theigzip.compress function, which should lead
  to less overhead.

• Fix a bug where streams that were passed to igzip_threaded.open where closed.

• Fix a bug where compression levels for IGzipFile where checked in read mode.
• Update statically linked ISA-L release to 2.31.0
• Fix an error that occurred in the__close__ function when a threaded
  writer was initialized with incorrect parameters.

• Fix a bug where append mode would not work when using
  igzip_threaded.open.

• Fix a bug where a filehandle remained opened whenigzip_threaded.open
  was used for writing with a wrong compression level.
• Fix a memory leak that occurred when an error was thrown for a gzip header
  with the wrong magic numbers.
• Fix a memory leak that occurred when isal_zlib.decompressobj was given a
  wrong wbits value.

• Fix a memory leak in the GzipReader.readall implementation.

• Make a special case for threads==1 inigzip_threaded.open for writing
  files. This now combines the writing and compression thread for less
  overhead.
• Maximize time spent outside the GIL forigzip_threaded.open writing.
  This has decreased wallclock time significantly.