setup-biome

name	setup-biome
description	Install Biome linter with Ultracite preset, create biome.jsonc config, and configure Claude Code Stop hook for auto-fix before finishing. Use when setting up linting, formatting, Biome, Ultracite, or code quality enforcement.

Setup Biome + Ultracite

• Biome linter/formatter + Ultracite opinionated preset
• Stop hook auto-fix lint/format on changed JS/TS files (skip noUnusedImports, avoid deletion loops)
• Strict: noConsole, cognitive complexity 15, noDeprecatedImports, restricted imports (moment/lodash/classnames/mobx/yup)

Steps

1. Install

bun add -D @biomejs/biome ultracite --yarn

2. Create biome.jsonc

From REFERENCE.md. Extend ultracite/biome/core + ultracite/biome/react. VCS git on. Test files re-enable noExplicitAny.

3. Package.json scripts

{
  "scripts": {
    "lint": "biome check .",
    "lint:fix": "biome check --write .",
    "lint:file": "biome check",
    "lint:fix:file": "biome check --write"
  }
}

4. Hook

Copy scripts/biome-autofix.sh -> .claude/hooks/. chmod +x. Add to Stop.

5. Verify

• bun run lint + bun run lint:fix work
• Hook executable + configured