@hardlydifficult/ts-config

A centralized package providing strict TypeScript, ESLint, and Prettier configurations for modern JavaScript and Next.js projects.

Installation

npm install @hardlydifficult/ts-config

Quick Start

Apply the shared ESLint and Prettier configurations to your project:

// eslint.config.js
import createEslintConfig from "@hardlydifficult/ts-config/eslint";
import prettierConfig from "@hardlydifficult/ts-config/prettier";

export default [
  ...createEslintConfig(import.meta.dirname),
  {
    rules: {
      // your overrides
    },
  },
];

// .prettierrc.js
import prettierConfig from "@hardlydifficult/ts-config/prettier";

export default prettierConfig;

TypeScript Configuration

Extend the base configuration in your tsconfig.json:

{
  "extends": "@hardlydifficult/ts-config/tsconfig.base.json",
  "compilerOptions": {
    "outDir": "./dist"
  },
  "include": ["src/**/*"]
}

ESLint Configuration

Exports a factory function that returns a flat ESLint configuration with strict TypeScript rules, import ordering, JSDoc requirements, and auto-fixable stylistic rules.

createEslintConfig(projectRoot)

Creates a fully-featured ESLint config for TypeScript projects.

| Parameter | Type | Description | |-----------|------|-------------| | projectRoot | string | Path to the project root directory; used by TypeScript ESLint for project service lookups |

import createEslintConfig from "@hardlydifficult/ts-config/eslint";

export default [
  ...createEslintConfig("path/to/project"),
];

Ignored Patterns

By default, ESLint ignores:

**/dist/**, **/node_modules/**, **/*.js,
**/tests/**, **/vitest.config.ts,
**/.next/**, **/.turbo/**, **/*.config.mjs

createNextEslintConfig(projectRoot, nextConfig)

Combines the base ESLint config with Next.js-specific rules.

| Parameter | Type | Description | |-----------|------|-------------| | projectRoot | string | Project root directory | | nextConfig | Linter.Config[] | Next.js ESLint config array (e.g., from @next/eslint-plugin-next) |

import createNextEslintConfig from "@hardlydifficult/ts-config/eslint-next";
import nextConfig from "@next/eslint-plugin-next/config";

export default [
  ...createNextEslintConfig(import.meta.dirname, nextConfig),
];

React Rules

| Rule | Level | Options | |------|-------|---------| | react/react-in-jsx-scope | off | — | | react/prop-types | off | — | | react/self-closing-comp | error | { component: true, html: true } | | react/jsx-boolean-value | error | "never" | | react/no-array-index-key | warn | — | | react/jsx-curly-brace-presence | error | { props: "never", children: "never" } |

Prettier Configuration

Exports a preconfigured Prettier settings object optimized for consistency across TypeScript/JavaScript projects.

prettierConfig

import prettierConfig from "@hardlydifficult/ts-config/prettier";

export default prettierConfig;
// {
//   semi: true,
//   singleQuote: false,
//   tabWidth: 2,
//   useTabs: false,
//   trailingComma: "es5",
//   bracketSpacing: true,
//   bracketSameLine: false,
//   arrowParens: "always",
//   endOfLine: "lf",
//   printWidth: 80,
//   quoteProps: "as-needed",
//   jsxSingleQuote: false,
//   proseWrap: "preserve",
//   htmlWhitespaceSensitivity: "css",
//   embeddedLanguageFormatting: "auto",
//   singleAttributePerLine: false,
// }

Usage with Prettier API

import prettierConfig from "@hardlydifficult/ts-config/prettier.js";
import { format } from "prettier";

const formatted = await format("console.log('Hello');", {
  ...prettierConfig,
  parser: "typescript",
});

TypeScript Configuration

Base compiler options for consistent builds across projects.

tsconfig.base.json

The base configuration includes strict type checking, ES2022 targeting, and modern module resolution:

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "CommonJS",
    "moduleResolution": "node",
    "lib": ["ES2022"],
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,
    "declaration": true,
    "declarationMap": true,
    "sourceMap": true,
    "resolveJsonModule": true,
    "isolatedModules": true
  }
}

Node Config (tsconfig.json)

Node-specific configuration extending the base config with:

• module: "Node16" and moduleResolution: "node16"
• outDir: "./dist" and rootDir: "./src"

Appendix

Rule Categories

The ESLint config enforces auto-fixable and non-auto-fixable rules:

| Auto-fixable | Non-auto-fixable | |--------------|------------------| | curly, no-useless-computed-key, prefer-const, quote-props | no-console (limited), no-restricted-globals, no-loop-func |

JSDoc Requirements

JSDoc is required for:

• FunctionDeclaration
• ClassDeclaration
• Public methods are excluded
• Constructors are not checked

Supported Node.js version: >=20.19.0
Peer dependencies required: eslint, typescript-eslint, eslint-plugin-import-x, eslint-plugin-jsdoc, eslint-plugin-unused-imports, eslint-config-prettier, @eslint/compat, @eslint/js