Quansight Labs is working with the Python runtime team at Meta and stakeholders across the ecosystem to jumpstart work on converting the libraries that make up the scientific Python and AI/ML stacks to work with the free-threaded (nogil) build of CPython 3.13. Additionally, we will look at libraries like PyO3 that are needed to interface with CPython from other languages.
Our initial goal is to ensure libraries at the bottom of the stack like NumPy, pybind11, and Cython are usable with free-threaded CPython. We will also be updating packaging tools like meson-python needed to support building wheels for free-threaded CPython. Once those tools and libraries are in a stable enough state, we will begin looking at libraries higher in the stack.
This repository is for coordinating ecosystem-wide work. We will use this repository to track, understand, and provide documentation for dealing with issues that we find are common across many libraries. Issues that are specific to a project should be reported in that project's issue tracker.
Currently we suggest building CPython from source using the latest version of
the CPython main branch. There is also a "bleeding-edge" branch integrating
several work-in-progress pull requests. You may have a more stable experience
using the nogil-integration
branch on Sam Gross' fork of
CPython. See the
build
instructions
in the CPython developer guide. You will need to install needed third-party
dependencies
before building. To build the free-threaded version of CPython, pass
--disable-gil to the configure script:
./configure --with-pydebug --disable-gilIf you will be switching Python versions often, it may make sense to
build CPython using pyenv. See
the pyenv folder in this repository for more details
managing free-threaded and non-free-threaded python installs with pyenv.