@jmlweb/oxlint-config-base

Base Oxlint configuration for JavaScript and TypeScript. Ports @jmlweb/eslint-config-base-js and @jmlweb/eslint-config-base to a linter that runs in milliseconds. Recommended linter.

✨ Features

• ⚡ Fast: Oxlint is written in Rust; type-aware rules run on the Go port of TypeScript
• 🔒 Strict TypeScript: typescript-eslint recommended, strict-type-checked and stylistic-type-checked rules
• 🟨 JavaScript and TypeScript in one config: ESLint recommended rules everywhere, TypeScript rules for .ts/.tsx/.mts/.cts
• 🎯 Same conventions: type over interface, no enums, no any, named exports only, no parameter mutation

📦 Installation

npm install --save-dev @jmlweb/oxlint-config-base oxlint oxlint-tsgolint

oxlint-tsgolint is only needed for type-aware rules.

🚀 Quick Start

Create oxlint.config.ts in your project root:

import baseConfig from '@jmlweb/oxlint-config-base';
import { defineConfig } from 'oxlint';

export default defineConfig({
  extends: [baseConfig],
  options: {
    typeAware: true,
  },
});

⚠️ Set typeAware in your own config. Oxlint reads options only from the root config, not from configs loaded through extends. Without it, type-aware rules are skipped silently.

💡 Examples

Before

enum Status {
  Active,
}

interface User {
  name: string;
}

export default function rename(user: User, data: any) {
  user.name = data.name;
  save(user);
}

Errors Reported

src/user.ts:1:1: error jmlweb(no-enum): Use const maps instead of enums
src/user.ts:1:6: error eslint(no-unused-vars): Enum 'Status' is declared but never used.
src/user.ts:5:1: error typescript(consistent-type-definitions): Use `type` instead of `interface`.
src/user.ts:9:8: error import(no-default-export): Prefer named exports
src/user.ts:9:50: error typescript(no-explicit-any): Unexpected `any`. Specify a different type.
src/user.ts:10:3: error eslint(no-param-reassign): Assignment to property of function parameter 'user'.
src/user.ts:10:15: error typescript(no-unsafe-assignment): Unsafe assignment of an any value.
src/user.ts:10:20: error typescript(no-unsafe-member-access): Unsafe member access .name on an `any` value.
src/user.ts:11:3: error typescript(no-floating-promises): Promises must be awaited, add void operator to ignore.

After

const STATUS = { ACTIVE: 'active' } as const;

type User = {
  name: string;
};

export const rename = async (user: User, name: string): Promise<User> => {
  const renamed = { ...user, name };
  await save(renamed);
  return renamed;
};

📋 Configuration Details

All files: Oxlint's correctness category as error, plus Oxlint equivalents of ESLint's recommended rules.

TypeScript files (**/*.{ts,tsx,mts,cts}):

• typescript-eslint recommended, strict and stylistic rules
• typescript-eslint strict-type-checked and stylistic-type-checked rules (with options.typeAware)
• Core rules the TypeScript compiler already checks (such as no-undef) turned off

Key Rules

| Rule | Level | Description | | ---------------------------------------- | ------- | ------------------------------------- | | typescript/no-explicit-any | error | No any | | typescript/consistent-type-imports | error | Inline type imports | | typescript/consistent-type-definitions | error | type over interface | | jmlweb/no-enum | error | No enums (use const maps) | | import/no-default-export | error | Named exports only | | eslint/no-param-reassign | error | No mutating parameters or their props | | eslint/no-unused-vars | error | Names prefixed with _ are allowed |

**/*.config.{ts,mts,cts} files may use default exports, since tools require them.

jmlweb/no-enum is a bundled JS plugin (@jmlweb/oxlint-config-base/plugin), because Oxlint has no no-restricted-syntax. Oxlint's JS plugin support is still in alpha.

Differences from @jmlweb/eslint-config-base

• No naming-convention: needs typescript-eslint's parser, which Oxlint cannot run
• No import sorting: @jmlweb/oxfmt-config-base sorts imports when formatting
• No Prettier conflict rules: this config enables no formatting rules
• No no-unsafe-enum-assignment: not available in Oxlint, and enums are banned anyway

🎯 When to Use

• ✅ Fast linting for new JavaScript or TypeScript projects (recommended)
• ✅ Migrating from @jmlweb/eslint-config-base or @jmlweb/eslint-config-base-js (maintenance mode)
• ✅ Type-aware rules without typescript-eslint's runtime cost

React: use @jmlweb/oxlint-config-react. Node.js: use @jmlweb/oxlint-config-node. Astro: keep @jmlweb/eslint-config-astro; Oxlint cannot lint .astro templates.

🔧 Extending the Configuration

import baseConfig from '@jmlweb/oxlint-config-base';
import { defineConfig } from 'oxlint';

export default defineConfig({
  extends: [baseConfig],
  options: {
    typeAware: true,
  },
  env: {
    node: true,
  },
  ignorePatterns: ['generated/**'],
  rules: {
    'jmlweb/no-enum': 'off',
  },
  overrides: [
    {
      files: ['**/*.test.ts'],
      rules: {
        'typescript/no-non-null-assertion': 'off',
      },
    },
  ],
});

Keep simple-import-sort

To keep eslint-plugin-simple-import-sort's order, set sortImports: false in your Oxfmt config and run the plugin through Oxlint:

import baseConfig from '@jmlweb/oxlint-config-base';
import { defineConfig } from 'oxlint';

export default defineConfig({
  extends: [baseConfig],
  jsPlugins: ['eslint-plugin-simple-import-sort'],
  rules: {
    'simple-import-sort/imports': 'error',
    'simple-import-sort/exports': 'error',
  },
});

📝 Usage with Scripts

{
  "scripts": {
    "lint": "oxlint",
    "lint:fix": "oxlint --fix"
  }
}

npm run lint      # Lint all files
npm run lint:fix  # Fix auto-fixable problems

📋 Requirements

• Node.js >= 22.12.0
• Oxlint >= 1.87.0
• TypeScript project with a tsconfig.json (for type-aware rules)

📦 Peer Dependencies

• oxlint (>=1.87.0)
• oxlint-tsgolint (>=7.0.0, optional): enables type-aware rules

🔗 Related Packages

• @jmlweb/oxlint-config-react - Extends this config for React
• @jmlweb/oxlint-config-node - Extends this config for Node.js
• @jmlweb/oxfmt-config-base - Oxfmt config, the formatter to pair with this linter
• @jmlweb/tsconfig-base - TypeScript config for type-aware linting
• @jmlweb/eslint-config-base - ESLint equivalent (maintenance mode)
• Migrate to Oxc - Move a project from the @jmlweb Prettier/ESLint packages
• Migrate from ESLint - Official guide

📄 License

MIT