Type check your Python codebase 15x faster with Pyrefly ⚡ Tools like MyPy and Pyright process files sequentially, so larger codebases lead to longer wait times. Pyrefly, Meta's Rust-based type checker, runs checks in parallel, keeping performance nearly constant as your codebase grows. Key features: • Re-checks only changed modules for faster incremental runs • Automatically infers types for variables and return values On the PyTorch codebase, Pyrefly completes a full check in 2.4 seconds, about 15x faster than Pyright and 20x faster than MyPy. --- 📬 I share 2 practical tips on practical tools for data and AI twice a week on Substack. Subscribe here: https://bit.ly/46fdOPl #Python #TypeChecking #Rust
Is Pyrefly faster than ty?
I think ty is even faster
I found that switching to parallel checks really cut down my debugging time, especially with bigger projects. Speeding up those feedback loops makes a real difference.
Are you sponsored by Meta and leaving out Ty (by the Astral team, creators of uv and Ruff)?..
🤯
Or.. just master Claude.
️📦 Link to the repository: https://github.com/facebook/pyrefly