# Lint and type checks

A step of the [Open source library](https://gradus.kazet.blog/tree/open-source-library) tree on Gradus, in the Quality bar area: Tests, CI, lint, coverage.

Page: https://gradus.kazet.blog/tree/open-source-library/step/lint-and-types

Enforce a formatter, a linter and type checks in CI so style and type errors never reach review.

Usually comes after: [CI across versions](https://gradus.kazet.blog/tree/open-source-library/step/ci-matrix).

## Prompt for your AI assistant

```
Add a formatter, a linter and a type checker with the configuration this ecosystem expects, a `lint` script that runs them all and a CI step that fails on any finding. Format the existing code once in a separate commit.
```

Every step of the tree: https://gradus.kazet.blog/tree/open-source-library/llms.txt