Pyrefly: Fast, IDE-friendly typing for Python - Talk Python to Me Ep. 523

Python typing got fast enough to feel invisible. Pyrefly is a new, open source type checker and IDE language server from Meta, written in Rust, with a focus on instant feedback and real-world DX. Today, we will dig into what it is, why it exists, and how it plays with the rest of the typing ecosystem. We have Abby Mitchell, Danny Yang, and Kyle Into from the Pyrefly project here to dive into the project.

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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 ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬

Kyle Into
Danny Yang
Abby Mitchell

▬▬▬▬ Links and resources from the show ▬▬▬▬▬▬▬▬▬▬▬▬

Abby Mitchell:   / abby-mitchell  
Danny Yang:   / yangdanny97  
Kyle Into:   / kyleinto  
Pyrefly: https://pyrefly.org
Pyrefly Documentation: https://pyrefly.org/en/docs/
Pyrefly Installation Guide: https://pyrefly.org/en/docs/installat...
Pyrefly IDE Guide: https://pyrefly.org/en/docs/IDE/
Pyrefly GitHub Repository: https://github.com/facebook/pyrefly
Pyrefly VS Code Extension: https://marketplace.visualstudio.com/...
Introducing Pyrefly: A New Type Checker and IDE Experience for Python: https://engineering.fb.com/2025/05/15...
Pyrefly on PyPI: https://pypi.org/project/pyrefly/
InfoQ Coverage: Meta Pyrefly Python Typechecker: https://infoq.com/news/2025/05/meta-p...
Pyrefly Discord Invite:   / discord  
Python Typing Conformance (GitHub): https://github.com/python/typing/tree...
Typing Conformance Leaderboard (HTML Preview): https://htmlpreview.github.io/?https:...

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