basilisk-python 0.33.0

Basilisk — the only Python type checker with a perfect 100% score on the official python/typing conformance results (https://github.com/python/typing/blob/main/conformance/results/results.html). A strict-by-default type checker and language server, written in Rust.

Basilisk

Basilisk is the only Python type checker with a perfect 100% score on the official python/typing conformance results — published on the Python typing repository's own leaderboard, ahead of Pyright, mypy, Pyrefly and ty. It is a strict-by-default type checker and complete language server, written in Rust.

• Website: https://www.basilisk-python.dev
• Conformance: https://www.basilisk-python.dev/docs/conformance/
• Source: https://github.com/Nimblesite/Basilisk

This package (basilisk-python) bundles the native basilisk binary as a Python wheel so it can be installed with pip/uv. It is the same binary distributed via GitHub Releases, Homebrew and Scoop — the wheel is a convenience for Python-managed environments, not a separate build.

The distribution is named basilisk-python because the name basilisk was already taken on PyPI. The installed command is still basilisk.

Install

pip install basilisk-python
# or
uv tool install basilisk-python

Use

basilisk check path/to/your_code.py
basilisk --version

Machine-readable output for tooling:

basilisk check path/to/your_code.py --output json --color never

Acknowledgments

The bundled binary is built on Ruff by Astral (MIT) and typeshed (Apache-2.0), among other open-source projects. Full third-party notices: https://github.com/Nimblesite/Basilisk/blob/main/NOTICES.

License

MIT