dask-stubs

dask-stubs provides third-party typing information for the Dask project. The goal is to fill the gaps left by the runtime package so that type checkers such as Mypy and Pyright can reason about typical Dask usage with confidence.

Project layout

The repository separates runtime helpers from the stub definitions:

• src/dask-stubs/ holds .pyi files that mirror the public Dask API.
• tests/typecheck/samples/ provides runtime-free Python snippets that mypy validates to guard the stubs.
• noxfile.py defines automation for linting, type checking, and stub sanity checks.

Quick start

1. Install development dependencies with uv (Python 3.12+):

   uv sync --group dev
   

2. Run the default automation via uv:

   uv run nox
   

   This runs Ruff, Mypy against the stubs, and the sample type-check tests.

Contribution guidelines

1. Prefer working against small slices of the API. It is easier to review and iterate on focused modules.
2. Each new stub should be paired with a usage example under tests/typecheck/samples/ (tested via mypy).
3. Keep the stubs faithful to the runtime signatures. Where the runtime is dynamic, fall back to Any but leave a TODO for future improvement.
4. Run the full uv run nox suite before sending a pull request.

See CONTRIBUTING.md for more detail on project conventions and coding standards.