pass enforces import cleanup only at commit time, not during development.
UI-Specific Configuration
For frontend projects with Tailwind CSS:
{
"css": {
"parser": {
"tailwindDirectives": true
}
},
"assist": {
"actions": {
"source": {
"useSortedAttributes": "on"
}
}
},
"linter": {
"rules": {
"nursery": {
"useSortedClasses": {
"fix": "safe",
"level": "warn",
"options": {
"attributes": ["classList"],
"functions": ["clsx", "cva", "cn", "tv", "tw"]
}
}
}
}
}
}
Biome
v2.4.0+
auto-enables CSS Modules parsing for
*.module.css
, so explicit
"cssModules": true
is usually unnecessary unless your project needs non-standard behavior.
Biome v2.4+ Notes
biome check
and
biome ci
now support
--only
and
--skip
for targeted rule/action runs.
biome check --write
now also applies formatting when applying fixes.
Config lookup now also supports hidden files:
.biome.json
and
.biome.jsonc
.
Config lookup now also supports user config directories (for example,
$HOME/.config/biome
on Linux/macOS equivalents).
New formatter option
formatter.trailingNewline
can disable trailing newline insertion.
HTML formatter behavior changed significantly in
v2.4.0
; expect larger diffs in HTML/Vue/Svelte/Astro if formatter support is enabled.
Troubleshooting
Common Issues
"No files matched"
Check
files.includes
patterns match your file structure.
Conflicting rules
Overrides are applied in order; later overrides take precedence.
Schema errors
Use local schema reference for IDE support:
"$schema": "./node_modules/@biomejs/biome/configuration_schema.json"
Biome vs Prettier
Biome handles JS/TS/JSON/CSS formatting. Use Prettier for:
Markdown (
.md
,
.mdx
)
YAML (
.yml
,
.yaml
)
Additional Resources
Examples
Working examples in
./examples/
:
./examples/base-config.jsonc
- Minimal library configuration
./examples/ui-config.jsonc
- Frontend project with Tailwind
./examples/lint-staged.js
- Pre-commit hook configuration
Full Documentation
For advanced features, migrations, or complete rule reference, consult the official Biome documentation via Context7 MCP:
Use context7 to fetch Biome documentation for [specific topic]
The official docs at biomejs.dev should be consulted as a last resort for features not covered here.