CPython is the reference implementation of the Python programming language.

In this document, I’ll summarise major speedups to the core parts of CPython in the following versions:

• 3.11

To get the most out of this, you should have knowledge of Python (especially in data model/dunder methods). Being able to read C is also a plus though not strictly necessary. Some knowledge of common data structures (hash tables, linkedlist, etc.) is also beneficial.

If you’re interested in the internals of CPython, and/or want to contribute, I believe this document has some educational value for you. If you find any parts hard to understand due to poor wording or plain inaccuracies, please open a PR!

Dive in by reading the index for 3.11.

I only list resources I’ve read before. I’m in no way affiliated with any of these works (except the devguide 😉):

• Complete beginner’s guide with visual diagrams: https://realpython.com/cpython-source-code-guide/
• High-level overview and deep-dive of many objects and parts of CPython: https://github.com/zpoint/CPython-Internals
• Like the previous guide, but arranged around topics: https://tenthousandmeters.com/
• CPython devguide: https://devguide.python.org/setup/