Biome

Biome replaces ESLint and Prettier with a single Rust binary that's 10-100x faster. Format 10,000 files in 0.3 seconds instead of 12. Lint them in 0.8 seconds instead of 45. One config file, one tool, one set of opinions.

The v2.3 release brings 423+ lint rules and type-aware linting — the gap with ESLint is closing fast. Migration from ESLint/Prettier is automated via biome migrate. 97% Prettier-compatible formatting means your codebase won't look different. Compared to ESLint + Prettier (more plugins, slower), Biome trades ecosystem for speed. Compared to dprint (fast formatter, no linting), Biome does both.

Use this on every new JavaScript/TypeScript project. For existing projects, evaluate whether your ESLint plugins are covered by Biome's built-in rules first. Skip this if you depend on framework-specific plugins (React hooks, Next.js) that Biome doesn't cover yet.

The catch: plugin ecosystem is the real gap. No eslint-plugin-react-hooks equivalent yet. Vue, Markdown, and YAML support is incomplete. And switching means your team learns a new tool — the speed gains need to outweigh the transition cost. Apache 2.0 license.