C code that doesn’t call into the CPython runtime isn’t constrained by the GIL. With 3.13t, conventional Python programs can now enjoy the same freedom. Cython 3.1 adds basic support for 3.13t.

Grok the faster interpreter in Python 3.14, learn what’s new in Python packages and PyPI, explore the new Python-to-C features in Cython 3.1, and seize the power of Python’s abstract base classes.