Compatibility Status Tracking
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 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 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.
Tip
It's early days for free-threaded support - bugs in CPython itself and in
widely used libraries with extension modules are being fixed every week.
It may be useful to use nightly wheels (when available) of packages
like cython or numpy, even if a first release is available on PyPI.
For example, you can install a NumPy nightly wheel by running:
pip install -i https://pypi.anaconda.org/scientific-python-nightly-wheels/simple numpy
| Project | Upstream issue | Tested in CI | PyPI release | First version with support | Nightly wheels | Nightly link |
|---|---|---|---|---|---|---|
| Bazel (rules-python) | n/a | 0.39.0 | ||||
| cffi | 1.18 | |||||
| cibuildwheel | 2.19 | |||||
| CMake | 3.30.0 | |||||
| ContourPy | 1.3.0 | |||||
| cryptography | ||||||
| Cython | 3.1.0 | |||||
| hatch | ||||||
| JAX | 1.4.2 | |||||
| joblib | 1.4.2 | |||||
| jupyterlab | ||||||
| matplotlib | 3.9.0 | |||||
| Meson | 1.5.0 | |||||
| meson-python | 0.16.0 | |||||
| ml-dtypes | ||||||
| mlir-python | ||||||
| multidict | ||||||
| mypyc | ||||||
| Nuitka | ||||||
| NumPy | 2.1.0 | |||||
| nanobind | 2.2.0 | |||||
| orjson | ||||||
| packaging | 24.0 | |||||
| pandas | 2.2.3 | |||||
| Pillow | 11.0.0 | |||||
| pip | 24.1 | |||||
| PyArrow | 18.0.0 | |||||
| pybind11 | 2.13 | |||||
| PyO3 | 1 | 0.23 | ||||
| PyTorch | 2.6.0 | |||||
| PyWavelets | 1.7.0 | |||||
| rpds-py | ||||||
| scikit-build-core | 0.9.5 | |||||
| scikit-image | 0.25.0 | |||||
| scikit-learn | 1.6.0 | |||||
| SciPy | 1.15.0 | |||||
| setuptools | 69.5.0 | |||||
| wrapt | 1.17.0.dev3 | |||||
| zstandard |