Biome Type Inference: A Look Behind the Scenes

Biome is an integrated linter/formatter for JavaScript/TypeScript, CSS, HTML and GraphQL.

We are now in the process of implementing TypeScript-like inference (not full type checking!) that allows us to enable type-informed lint rules. This is similar to typescript-eslint except instead of using tsc we attempt to implement the inference ourselves.

This post describes our progress thus far, with a detailed overview of our type architecture.