Compatibility Status Tracking - Python Free-Threading Guide

This page tracks the status of packages for which we're aware of active work on free-threaded support. It contains packages with extension modules, as well as build tools and packages that needed code changes specifically to support free-threading. Note that pure Python code works without changes by design, hence this page does not aim to track pure Python packages.

We are updating this tracking table manually and including links to nightlies and project-specific issue links. There is also an

automatically updated tracker

that pulls in information for a wider range of packages, but only tracks whether or not they have wheels on PyPI.

If you are using conda-forge, you can track the packages still waiting to be migrated

on the conda-forge website

.

If there's a bug related to free-threading in a library you use, please open an issue on the corresponding issue tracker or post a comment on the corresponding free-threading support tracking issue (see table below). If an issue spans multiple projects or there's an ecosystem-wide point to discuss, please open an issue on

this issue tracker

.

ProjectUpstream issueTested in CIPyPI releaseFirst version with supportNightly wheelsNightly linkaiohttp3.13.0asv0.6.6Bazel (rules-python)

1

0.39.0argon2-cffi-bindings25.1.0Boost.Python1.91.0bcrypt4.3.0blisbottleneck1.5.0brotlibrotlicffi1.2.0.1cffi2.0.0charset-normalizer3.4.6cibuildwheel2.19CMake3.30.0conda24.11.0connector-xContourPy1.3.0cramjam2.11.0cryptography46.0.0cuda-pythoncuda-tile1.4.0cupy14.1.0CuTe DSL

2

4.5.2cymem2.0.13Cython3.1.0datafusion54.0.0fastrlockfrozenlist1.6.0greenlet

3

3.5.2grpciohatch1.16.3h5py3.16.0hf-xet1.2.0httptools0.8.0hypothesis6.135.32JAX0.5.1joblib1.4.2jupyter_client

4

8.7.0jupyterlab

5

4.6.0kiwisolver1.4.8kornia-rs0.1.9LibCST1.8.0llguidance1.6.0llvmlite0.47.0lxml7.0.0lz44.4.5mamba2.3.2marisa-trie1.3.0markupsafe3.0.0matplotlib3.9.0maturin1.7.5Meson1.5.0meson-python0.16.0ml-dtypes0.5.1mlir-python20.1.0mlx0.32.1multidict6.2.0msgpack1.2.0msgspec0.20.0murmurhash1.0.15mypyc1.20.0nanobind2.2.0ndindex1.10.0netcdf41.7.4nox2025.10.14Numba0.65.0Nuitkanumexpr2.11.0NumPy2.1.0nvidia-cudnn-frontend1.23.0nvImageCodec0.4.0ONNX1.18.0OpenCVopenai-harmonyorjsonoutlines-corepackaging24.0pandas2.2.3Pillow11.0.0pip24.1Pixi0.39.5polarspreshed3.0.11propcache0.3.0protobufpsutil7.1.2psycopgpy-radix1.1.0PyArrow18.0.0PyAV15.1.0pybind112.13pycares4.11.0pycocotools2.0.10pycryptodome3.23.0pydantic2.11.0pydantic-core2.29.0pygit21.19.0PyNaCl1.6.0PyO3

6

0.23PyObjC11.0PyTables3.11.0Pythran0.18.0PyTorch2.6.0PyWavelets1.7.0pywinpty2.0.15PyYAML6.0.3PyZMQ27.0.0QuantLib1.42RapidFuzz3.14.3rpds-py0.22.3ruamel.yaml.clibrust-numpy

6

0.24.0safetensorsscikit-build-core0.9.5scikit-image0.25.2scikit-learn1.6.0SciPy1.15.0sentencepiece0.2.1setproctitle1.3.6setuptools69.5.0setuptools-rust1.11.0SGLangShapely2.1.0soundfile0.14.0spacySpack2026.03.0sqlalchemy2.0.45srsly2.5.2statsmodelsStringZilla5.0.4SWIG

7

4.4.0thrift0.23.0tiktoken0.12.0tokenizerstorchaotorchgeo0.9.0tornadotox4.26.0Tritonuv0.4.24uvloop0.22.1ultrajson5.13.0vLLMwrapt1.17.0xformers0.0.35xgrammar0.1.31xxhash3.6.0yappiyarl1.20.0zstandard

8

———
Release available in the

Bazel Central Registry

Support is provided through the nvidia-cutlass-dsl-libs-base and nvidia-cutlass-dsl-libs-cu13 packages.

It is fully supported on Python 3.15t and above, on 3.14t it may crash at runtime exit.

Functional, CI flaky test and disabled: blocked on msgpack

Functional, CI flaky test and disabled: blocked on jupyter_client & msgpack

Rust library released on

crates.io

Release available on the

SWIG website

, or use the git tag on

its GitHub repository

Python 3.14 includes the new

compression.zstd module

, backports are available under

backport.zstd

for Python 3.9-3.13