Zuban – The Python Language Server for Professionals

A Mypy-compatible Python Language Server built in Rust

Extremely fast. Generally 20-200x faster than Mypy - and optimized for lower memory usage.

All relevant LSP features are implemented, completions, goto, references, diagnostics and rename included.

Developed by the creator of Jedi, ZubanLS applies 14 years of experience in Python auto-completion and static analysis.

As a Beta release, some false positives are expected. Issues will be addressed promptly.

Commercial licenses are available for organizations that prefer not to comply with the AGPL. Contact us for commercial licensing options.

In 2012, I created Jedi—a Python auto-completion library that eventually reached millions of users and billions of downloads. But as the ecosystem evolved, one limitation became clear: speed. Jedi’s architecture couldn’t deliver the performance needed for large-scale projects.

In 2020, I started over—with everything I’d learned—building ZubanLS from the ground up in Rust. After five years of full-time work, ZubanLS is now the first truly fast Python language server.

ZubanLS is built for professionals who need precision, reliability and speed. It addresses long-standing issues in tools like Mypy and Pyright by focusing on performance without compromising features. Support for Django, go-to-definition, completions, and all other important LSP features have been implemented. The goal: a tool for perfectionists with deadlines.

If something essential is missing for your use case, feel free to reach out—we’re open to implementing features based on real-world demand.