@gaia-react/lint

GAIA's lint configuration.

Install

pnpm add -D @gaia-react/lint eslint prettier typescript

Quick start

The block below is the actual eslint.config.mjs shipped by GAIA. Copy it verbatim and adjust the override block at the bottom for your project.

import gaiaLint from '@gaia-react/lint';
import {defineConfig} from 'eslint/config';

export default defineConfig([
  ...gaiaLint.ignores({gitignore: '.gitignore'}),
  ...gaiaLint.base,
  ...gaiaLint.react,
  ...gaiaLint.testing,
  ...gaiaLint.storybook,
  ...gaiaLint.playwright,
  ...gaiaLint.styleHygiene,
  ...gaiaLint.guardrails,
  ...gaiaLint.betterTailwind({
    entryPoint: './app/styles/tailwind.css',
    ignore: ['plain-link', 'plain-table'],
  }),
  ...gaiaLint.prettier,
]);

Exports

| Export | Shape | Includes | Required? | | ---------------- | -------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | | base | Linter.Config[] | JS recommended, TypeScript (typescript-eslint), import-x, eslint-comments, prefer-arrow-functions, lodash/underscore guard | required | | react | Linter.Config[] | eslint-plugin-react, react-hooks, jsx-a11y, GAIA-specific React rules | required for React apps | | styleHygiene | Linter.Config[] | canonical, perfectionist, unicorn, unused-imports, check-file | required | | guardrails | Linter.Config[] | no-enum (custom), no-switch (custom), no-relative-import-paths, sonarjs, eslint-comments, import-x, prefer-arrow-functions | required | | testing | Linter.Config[] | Vitest + Testing Library config scoped to *.test.* and test/ | optional | | storybook | Linter.Config[] | eslint-plugin-storybook scoped to *.stories.* | optional | | playwright | Linter.Config[] | eslint-plugin-playwright scoped to e2e/ | optional | | prettier | Linter.Config[] | eslint-config-prettier — must be last to disable formatting rules | required if using Prettier | | betterTailwind | (opts) => Linter.Config[] | eslint-plugin-better-tailwindcss factory; takes entryPoint (path to Tailwind entry CSS) and optional ignore (class names to skip) | optional | | ignores | (opts?) => Linter.Config[] | includeIgnoreFile helper plus GAIA defaults; takes optional gitignore (path) and extra (string[]) | recommended |

The default export bundles every named export:

import gaiaLint from '@gaia-react/lint';
// gaiaLint.base, gaiaLint.react, gaiaLint.betterTailwind({...}), ...

Override patterns

Flat config is last-write-wins. Append override blocks after the gaia-lint spreads to disable, change, or scope rules.

Disable a rule globally

export default defineConfig([
  ...gaiaLint.base,
  ...gaiaLint.react,
  {rules: {'sonarjs/cognitive-complexity': 'off'}},
]);

Override on specific globs

export default defineConfig([
  ...gaiaLint.base,
  ...gaiaLint.react,
  {
    files: ['app/legacy/**'],
    rules: {'sonarjs/cognitive-complexity': 'off'},
  },
]);

Swap parser options

export default defineConfig([
  ...gaiaLint.base,
  {
    languageOptions: {
      parserOptions: {project: './tsconfig.eslint.json'},
    },
  },
]);

Add an extra plugin

import myPlugin from 'eslint-plugin-my-plugin';

export default defineConfig([
  ...gaiaLint.base,
  ...gaiaLint.react,
  {
    plugins: {'my-plugin': myPlugin},
    rules: {'my-plugin/some-rule': 'error'},
  },
]);

Peer dependencies

eslint, prettier, and typescript are declared as peer dependencies so consumers control their own versions and a single resolved copy of each is installed in node_modules. Every other plugin (eslint-plugin-react, typescript-eslint, eslint-plugin-import-x, etc.) ships as a direct dependency of @gaia-react/lint so consumers don't have to install or upgrade them individually.

Supported versions:

• eslint ^9.0.0
• prettier ^3.0.0
• typescript ^5.0.0 || ^6.0.0

Custom rules included

Two rules are implemented inside this package and ship as part of guardrails.

no-enum

Forbids TypeScript enum declarations. Enums emit runtime code, are not tree-shakeable, conflate value and type space, and have well-known footguns around numeric vs string enums and reverse mappings. Use a const object plus a derived union type instead.

// flagged
enum Status {
  Active,
  Inactive,
}

// preferred
const Status = {
  Active: 'active',
  Inactive: 'inactive',
} as const;
type Status = (typeof Status)[keyof typeof Status];

Opt out for a file or block:

{files: ['src/legacy/**'], rules: {'no-enum/no-enum': 'off'}}

no-switch

Forbids switch statements. They are an early-return / lookup-map / if chain in disguise and are easy to misuse (fallthrough, missing default, shadowed locals across cases). Replace with a lookup object, an early return chain, or a discriminated-union exhaustiveness check.

Opt out for a file or block:

{files: ['src/parser/**'], rules: {'no-switch/no-switch': 'off'}}

Tailwind / better-tailwindcss factory

betterTailwind is a factory because the underlying plugin needs to know where your Tailwind entry CSS file lives.

...gaiaLint.betterTailwind({
  entryPoint: './app/styles/tailwind.css',
  ignore: ['plain-link', 'plain-table'],
}),

| Option | Type | Required | Description | | ------------ | ---------- | -------- | -------------------------------------------------------------------------------------------- | | entryPoint | string | yes | Path to your Tailwind entry CSS, used by the plugin to resolve the active class set. | | ignore | string[] | no | Class names the plugin should ignore in no-unregistered-classes (e.g. design-system tokens, plain-* utility shims). |

Ignores factory

ignores produces a leading flat-config block that merges your .gitignore plus GAIA defaults.

...gaiaLint.ignores({
  gitignore: '.gitignore',
  extra: ['coverage/**', '**/*.generated.ts'],
}),

| Option | Type | Required | Description | | ---------- | ---------- | -------- | ---------------------------------------------------------------------------------------------------- | | gitignore| string | no | Path to a .gitignore file (relative to cwd or absolute). Patterns are merged via includeIgnoreFile. | | extra | string[] | no | Extra ignore globs merged with GAIA defaults. |

GAIA folder conventions baked into check-file

The check-file rules in styleHygiene encode GAIA's folder layout:

• app/components/** — component file naming
• app/pages/** — route/page file naming
• app/hooks/** — hook file naming (use-*.ts)
• test/** — test harness naming

If your project uses a different layout, override the relevant check-file/* rules after the styleHygiene spread:

export default defineConfig([
  ...gaiaLint.base,
  ...gaiaLint.styleHygiene,
  // Project uses src/ instead of app/
  {
    files: ['src/components/**'],
    rules: {
      'check-file/filename-naming-convention': [
        'error',
        {'src/components/**/*.{ts,tsx}': 'PASCAL_CASE'},
      ],
    },
  },
]);

Or disable the GAIA check-file block entirely and reapply your own:

{rules: {'check-file/folder-naming-convention': 'off'}}

Versioning policy

This package follows SemVer.

• Patch. Plugin version bumps that do not change rule defaults, internal refactors, README fixes.
• Minor. New rules added, new options exposed on factories, new named exports, opt-in changes that do not break existing consumer configs.
• Major. Engine swaps (ESLint → Biome), eslint major version bumps, removal/rename of named exports, default-rule changes that introduce new errors in previously-clean code.

License

MIT