Catching up with the Python Typing Council - Talk Python to Me Ep. 539

You're adding type hints to your Python code, your editor is happy, autocomplete is working great. But then you switch tools and suddenly there are red squiggles everywhere. Who decides what a float annotation actually means? Or whether passing None where an int is expected should be an error? It turns out there's a five-person council dedicated to exactly these questions -- and two brand-new Rust-based type checkers are raising the bar. On this episode, I sit down with three members of the Python Typing Council -- Jelle Zijlstra, Rebecca Chen, and Carl Meyer -- to learn how the type system is governed, where the spec and the type checkers agree and disagree, and get the council's official advice on how much typing is just enough. ▬▬▬▬ About the podcast ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ This video is the uncut, live recording of the Talk Python To Me podcast ( https://talkpython.fm ). We cover Python-focused topics every week and publish the edited and polished version in audio form. Subscribe in your podcast player of choice (100% free) at https://talkpython.fm/subscribe. ▬▬▬▬ Guests ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ Jelle Zijlstra Rebecca Chen Carl Meyer ▬▬▬▬ Links and resources from the show ▬▬▬▬▬▬▬▬▬▬▬▬ Typing Council: https://github.com/python/typing-council?tab=readme-ov-file typing.python.org: http://typing.python.org details here: https://github.com/python/typing-council?tab=readme-ov-file#decision-making-considerations ty: https://docs.astral.sh/ty/ pyrefly: https://pyrefly.org conformance test suite project: https://github.com/python/typing/tree/main/conformance typeshed: https://github.com/python/typeshed Stub files: https://mypy.readthedocs.io/en/stable/stubs.html Pydantic: http://pydantic.dev Beartype: https://github.com/beartype/beartype TOAD AI: https://github.com/batrachianai/toad PEP 747 – Annotating Type Forms: https://peps.python.org/pep-0747/ PEP 724 – Stricter Type Guards: https://peps.python.org/pep-0724/ Python Typing Repo (PRs and Issues): https://github.com/python/typing ▬▬▬▬ Dive deeper ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ Listen to the Talk Python To Me podcast at https://talkpython.fm and explore over 275 hours of Python courses at https://training.talkpython.fm/courses. ▬▬▬▬ Follow us on Social ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬ Mastodon: Michael - https://fosstodon.org/@mkennedy & Talk Python - https://fosstodon.org/@talkpython Bluesky: Michael - https://bsky.app/profile/mkennedy.codes & Talk Python - https://bsky.app/profile/talkpython.fm X: Michael - https://x.com/mkennedy & Talk Python - https://x.com/talkpython