It works. The nogil fork is officially dead. For CPU-bound threaded workloads (think web scraping, data processing, or pandas aggregations), teams are reporting 2x to 4x speedups without rewriting a single line of multiprocessing code.
— Your friendly local Pythonista
So only 1 in 5 production environments is on 3.13. Why? The free-threaded build requires recompiling C extensions, and many CI/CD pipelines haven't updated their base Docker images. python 3.13 news today november 2025