Neil Mitchell: Pyrefly: Type Checking 1.8 Million Lines of Python Per Second
How do you type-check 1.8 million lines of Python per second? Neil Mitchell explains how Pyrefly (a new Python type checker) achieves this level of performance.
Python's optional type system has grown increasingly sophisticated since type annotations were introduced in 2014, now featuring generics, subtyping, flow types, inference, and field refinement. This talk explores how Pyrefly models and validates this complex type system, the architectural choices behind it, and the performance optimizations that make it blazingly fast.
Learn more: https://pyrefly.org