We’re building a new static type checker for Python, from scratch, in Rust. From a technical perspective, it’s probably our most ambitious project yet. We’re about 800 PRs deep!
Like Ruff and uv, there will be a significant focus on performance. The entire system is designed to be highly incremental so that it can eventually power a language server (e.g., only re-analyze affected files on code change). [...]
We haven't publicized it to-date, but all of this work has been happening in the open, in the Ruff repository.
Recent articles
- Phoenix.new is Fly's entry into the prompt-driven app development space - 23rd June 2025
- Trying out the new Gemini 2.5 model family - 17th June 2025
- The lethal trifecta for AI agents: private data, untrusted content, and external communication - 16th June 2025