Biome v2.0–v2.4 Knowledge Patch

You know Biome through v1.6.x: basic lint/format for JS/TS/JSX/TSX/JSON, biome.json config, biome check/format/lint commands, Prettier-compatible formatter, ~200 lint rules, partial Astro/Svelte/Vue support.

This patch covers v2.0–v2.4 (2025-06-17 – 2026-02-10).

Index

Topic	Reference	Key changes
Configuration & Migration	references/config-and-migration.md	files.includes replaces ignore/include, config discovery, nested configs for monorepos
Linting & Plugins	references/linting-and-plugins.md	Linter domains, type-aware linting, suppression comments, GritQL plugins
Formatting & Language Support	references/formatting-and-languages.md	Assists, HTML formatter, embedded snippets, Vue/Svelte/Astro, Tailwind v4 CSS

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Quick Reference — Breaking Changes

files.includes replaces files.ignore and files.include

This is the most impactful v2 breaking change. Both fields merged into one.

{
  "files": {
    "includes": [
      "**",
      "!**/generated",
      "!!**/dist"
    ]
  }
}

• Globs no longer auto-prepend **/ — you must write full patterns
• * no longer matches /
• Globs are relative to config file location, not working directory
• ! prefix — skip formatting/linting but still index for types (v2.3)
• !! prefix — completely exclude from all Biome operations (v2.3)

See references/config-and-migration.md for config discovery and monorepo setup.

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Quick Reference — Linter Domains

Framework-specific rule groups that auto-activate based on package.json dependencies.

Domain	Activates for
react	React projects
next	Next.js projects
solid	SolidJS projects
vue	Vue projects
playwright	Playwright tests
drizzle	Drizzle ORM
qwik	Qwik projects
project	Module graph analysis (import cycles, unresolved imports)
types	Type inference rules (no TS compiler needed)
test	Test-specific rules

{
  "linter": {
    "domains": {
      "react": "recommended",
      "next": "all",
      "project": "recommended",
      "types": "recommended"
    }
  }
}

Values: "recommended" (stable rules), "all" (including nursery), "none". CLI: --only=project, --skip=test.

See references/linting-and-plugins.md for type-aware linting, suppression comments, and GritQL plugins.

---

Quick Reference — Assists

New category between formatter and linter. Actions without diagnostics. Import organizing moved here from linter.

{
  "assist": {
    "actions": {
      "source": {
        "organizeImports": "on",
        "useSortedKeys": { "level": "on", "options": { "groupByNesting": true } },
        "useSortedAttributes": "on",
        "noDuplicateClasses": "on"
      }
    }
  }
}

Import organizer revamp: cross-chunk sorting, import merging from same module, custom ordering, export organizing, import attribute sorting.

See references/formatting-and-languages.md for HTML formatter, embedded snippets, and framework support.