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repobuddy

Override a rule or formatter setting

Settings in your own biome.json win over the ones in the config you extend. This guide shows each kind of change. Each example was run with Biome 2.5.15.

Steps

Section titled “Steps”

  1. Extend the preset first, then add your own keys below it.

    biome.json
    {
      "extends": ["@repobuddy/biome"]
    }

  2. Change a formatter setting. Name the key the preset sets.

    {
      "extends": ["@repobuddy/biome"],
      "formatter": { "indentStyle": "space", "indentWidth": 2 },
      "javascript": { "formatter": { "semicolons": "always" } }
    }

    With this config, biome format rewrites tab-indented code to two spaces.

  3. Change a rule level.

    {
      "extends": ["@repobuddy/biome"],
      "linter": { "rules": { "suspicious": { "noExplicitAny": "warn" } } }
    }

    noExplicitAny is off in both presets. This sets it to warn.

  4. Change a rule only for some files, with overrides.

    {
      "extends": ["@repobuddy/biome"],
      "overrides": [
        {
          "includes": ["scripts/**"],
          "linter": { "rules": { "suspicious": { "noConsole": "off" } } }
        }
      ]
    }

    console.log is still an error in src/, and allowed in scripts/.

  5. Change a rule’s options. State the whole option, because an option you set replaces the preset’s value.

    {
      "extends": ["@repobuddy/biome"],
      "linter": {
        "rules": {
          "suspicious": {
            "noConsole": { "level": "error", "options": { "allow": ["log", "info"] } }
          }
        }
      }
    }

    With this config, console.log is allowed and console.warn is an error. The preset’s allow list of info, warn, error, and others is gone.

Extending order

Section titled “Extending order”

extends is an array, and later entries win over earlier ones. Your own keys, written in the same file, win over everything in extends.

{
  "extends": ["@repobuddy/biome", "./team.json"]
}

With ./team.json last, its settings override the preset’s. Swapping the order makes the preset override ./team.json. Verified with suspicious/noConsole: with the preset last, the preset’s allow list applied.

See the Biome configuration reference for the full merge rules.

Verify

Section titled “Verify”

Run biome check and confirm the finding you changed appears, or stops appearing, at the level you set.

Section titled “Related”