Issues

• C extension should reject ext_hook=None consistently with the Python fallback

  msgpack/msgpack-python#762 · by Filter by author methane was closed on Oct 30, 2026

• Sprunke Phase 17 demo Zane empire's take

  msgpack/msgpack-python#746 · by Filter by author veroloe74-rgb was closed on Oct 7, 2026

• Unpacker.unpack() segfaults after an incomplete skip()

  msgpack/msgpack-python#734 · by Filter by author marinelay was closed on Oct 1, 2026
  1

• Python 3.15 support

  msgpack/msgpack-python#725 · by Filter by author Houbein was closed on Aug 27, 2026
  1

• Heap buffer overflow in Packer(buf_size=…) with an unstable __index__

  msgpack/msgpack-python#723 · by Filter by author marinelay was closed on Aug 14, 2026

• unpackb() may return corrupted ExtraData.extra for non-contiguous input

  msgpack/msgpack-python#720 · by Filter by author marinelay was closed on Aug 5, 2026
  2

• early 1.2.1 feedback

  msgpack/msgpack-python#699 · by Filter by author ThomasWaldmann was closed on Jun 18, 2026
  1

• Incorrect docstring for Unpacker.read_size

  msgpack/msgpack-python#697 · by Filter by author senyai was closed on Jun 19, 2026

• Unpacker: datetime silent overflow in timestamp=3 mode.

  msgpack/msgpack-python#696 · by Filter by author methane was closed on Jun 19, 2026

• Use-after-free when a decode hook re-enters feed()

  msgpack/msgpack-python#695 · by Filter by author methane was closed on Jun 24, 2026

• msgpack.fallback DEFAULT_RECURSE_LIMIT smaller than python 3.10 default

  msgpack/msgpack-python#674 · by Filter by author rsiemens was closed on May 22, 2026
  2

  

• setuptools >= 80.9.0 build system requirement causes issues for downstream packagers

  msgpack/msgpack-python#651 · by Filter by author tiran was closed on Oct 9, 2025
  3

• Request for wheels for Python 3.14rc2 for testing purposes

  msgpack/msgpack-python#644 · by Filter by author mborsetti was closed on Oct 8, 2025
  2

• Support for free-threaded CPython

  msgpack/msgpack-python#635 · by Filter by author m-clare was closed on May 28, 2025

• msgpack._version still exists and is wrong

  msgpack/msgpack-python#632 · by Filter by author ThermodynamicBeta was closed on Apr 25, 2025
  3

• Support for set Serialization

  msgpack/msgpack-python#631 · by Filter by author DanielKirshner was closed on Apr 18, 2025
  4

• Failed install on iot venusos system on RaspberryPi 3B+ (ARMv7 r4)

  msgpack/msgpack-python#630 · by Filter by author midnightblock24 was closed on Dec 30, 2024
  3

• Error during unpacking (ExtraData): unpack(b) received extra data.

  msgpack/msgpack-python#629 · by Filter by author haarshdev was closed on Dec 17, 2024
  1

• 1.1.0 Pyodide Compatibility

  msgpack/msgpack-python#627 · by Filter by author riyavsinha was closed on Oct 29, 2024
  3

• Builds on no-GIL interpreters, but not fully supported yet

  msgpack/msgpack-python#613 · by Filter by author clin1234 was closed on Jun 4, 2026
  23

• Dict memory leak in Python 3.12.x / msgpack 1.0.x

  msgpack/msgpack-python#612 · by Filter by author amachanic was closed on May 31, 2025
  7

• Build failure with MSVC v17.10.0-pre.4.0 and Python 3.13

  msgpack/msgpack-python#597 · by Filter by author clin1234 was closed on May 4, 2024

• New release

  msgpack/msgpack-python#595 · by Filter by author uyha was closed on Apr 25, 2024
  2

• Python 3.13: compile error on Ubuntu 20.04

  msgpack/msgpack-python#593 · by Filter by author tristanlatr was closed on May 4, 2024
  5

• msgpack's C extension is not built.

  msgpack/msgpack-python#586 · by Filter by author ThomasWaldmann was closed on Mar 10, 2024
  8