Add packaged Rust toolchain file

The repository already has pyrefly_wasm/rust-toolchain as a symlink to ../pyrefly/rust-toolchain, and the pyrefly package metadata includes a rust-toolchain file in source distributions. The target file was missing, leaving the symlink broken.

Swatinem/rust-cache scans rust-toolchain files when constructing its environment hash, so the broken symlink made cache setup emit ENOENT in the branch workflow runs and prevented clean cache restore/save behavior. Add the missing stable toolchain file so the symlink resolves and the cache key can include the toolchain input normally.
1 file changed
tree: 1b0645dd562f9d080ec333bbd517730940044cb1
  1. .cargo/
  2. .claude/
  3. .github/
  4. .llms/
  5. .vscode/
  6. conformance/
  7. crates/
  8. lsp/
  9. pyrefly/
  10. pyrefly_wasm/
  11. release_notes/
  12. schemas/
  13. scripts/
  14. tensor-shapes/
  15. test/
  16. website/
  17. .gitattributes
  18. .gitignore
  19. action.yml
  20. AGENTS.md
  21. ARCHITECTURE.md
  22. Cargo.lock
  23. Cargo.toml
  24. CODE_OF_CONDUCT.md
  25. CONTRIBUTING.md
  26. debug.html
  27. empty.py
  28. LICENSE
  29. package-lock.json
  30. README.md
  31. rust-toolchain.toml
  32. rustfmt.toml
  33. TENSOR_SHAPES_CONTRIBUTING.md
  34. test.py
  35. version.bzl
  36. yarn.lock
README.md

Pyrefly: A fast type checker and language server for Python with powerful IDE features

pyrefly PyPI VS Code Open VSX Discord License: MIT

Pyrefly is a type checker and language server for Python, which provides lightning-fast type checking along with IDE features such as code navigation, semantic highlighting, and code completion. It is available as a command-line tool and an extension for popular IDEs and editors such as VSCode, Neovim, Zed, and more.

See the Pyrefly website for full documentation and how to add Pyrefly to your editor of choice.

Pyrefly's current development status is stable.

Key Features

  • Fast. Pyrefly checks over 1.85 million lines of code per second, type checking projects like PyTorch 15x faster than Mypy and Pyright. In the IDE, rechecks typically complete in under 10 milliseconds after saving a file.
  • Production-proven at scale. Pyrefly is the default type checker for Instagram's 20-million-line Python codebase at Meta, and has been adopted by large open source projects including PyTorch and JAX.
  • Full-featured language server. Code navigation, autocomplete, hover information, inlay hints, semantic highlighting, and more, with consistent results across the CLI and your editor of choice.
  • Understands real-world Python. Built-in support for frameworks like Pydantic and Django, with model validation, field types, and autocomplete that work out of the box.
  • Adoption-ready. Migrate from Mypy or Pyright with pyrefly init, silence existing errors with pyrefly suppress, and generate type annotations with pyrefly infer. Start with one file and expand at your own pace.

Getting Started

Version Policy

Pyrefly releases new minor versions (1.x.0) monthly and patch versions in between as-needed for critical fixes. Pyrefly does not follow strict semantic versioning: minor versions contain more significant changes than patch versions, but any version may introduce new type errors and other breaking changes. The pyrefly suppress command can be used to easily silence errors when upgrading to a new version.

Getting Involved

If you have questions or would like to report a bug, please create an issue.

See our contributing guide and architecture overview for information on how to contribute to Pyrefly.

Join our Discord to chat about Pyrefly and types. This is also where we hold biweekly office hours.