Pyrefly: Fast, IDE-friendly typing for Python

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 Pyrefly here to dive into the project.

Episode sponsors

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Links from the show

Abby Mitchell: linkedin.com
Danny Yang: linkedin.com
Kyle Into: linkedin.com

Pyrefly: pyrefly.org
Pyrefly Documentation: pyrefly.org
Pyrefly Installation Guide: pyrefly.org
Pyrefly IDE Guide: pyrefly.org
Pyrefly GitHub Repository: github.com
Pyrefly VS Code Extension: marketplace.visualstudio.com
Introducing Pyrefly: A New Type Checker and IDE Experience for Python: engineering.fb.com
Pyrefly on PyPI: pypi.org
InfoQ Coverage: Meta Pyrefly Python Typechecker: infoq.com
Pyrefly Discord Invite: discord.gg
Python Typing Conformance (GitHub): github.com
Typing Conformance Leaderboard (HTML Preview): htmlpreview.github.io

Watch this episode on YouTube: youtube.com
Episode #523 deep-dive: talkpython.fm/523
Episode transcripts: talkpython.fm

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