Show HN: A Python Language Server, Mypy-compatible
10 months ago
- #Language Server
- #Python
- #Rust
- A Mypy-compatible Python Language Server built in Rust.
- Standards-compliant with a fully featured type system.
- Unparalleled performance: 20-200x faster than Mypy with optimized memory usage.
- Currently supports diagnostics; features like completions and go-to-definition are in development.
- Developed by the creator of Jedi, leveraging 14 years of Python auto-completion and static analysis experience.
- Alpha release with some expected false positives; beta release coming soon.
- Works in VSCode, Vim, and all other LSP-compatible editors including Helix, NeoVIM, SublimeText, Emacs, Zed, etc.
- Key features: Mypy config compatibility, error recovery, incremental checking, file watching, Python 3.13 support.
- Advanced code understanding: passes >95% of Mypy's tests, supports various imports, type narrowing, and more.
- Performance optimized: written in Rust, significantly faster than Mypy, minimal memory usage.
- Comprehensive type system support including TypeVar, Overloads, Dataclasses, Protocols, Literal Types, and more.
- Includes executables: zubanls (language server) and zmypy (Mypy replacement), compatible with Linux, Mac, and Windows.
- Free during alpha; pricing post-alpha based on code size—free for most users, paid for large codebases.
- Built by David Halter, founder of Jedi, addressing speed limitations in existing tools.
- Aimed at professionals needing precision, reliability, and speed; future support for Django, LSP features underway.
- Initial 2025 release may not cover all needs; open to feature requests based on real-world demand.