@hardlydifficult/ts-config

Opinionated ESLint, Prettier, and TypeScript config package with Next.js support.

Installation

npm install @hardlydifficult/ts-config

Quick Start

// .eslintrc.cjs
import createConfig from "@hardlydifficult/ts-config/eslint";
import createNextConfig from "@hardlydifficult/ts-config/eslint-next";
import prettierConfig from "@hardlydifficult/ts-config/prettier";

export default [
  ...createConfig(__dirname),
  // For Next.js projects:
  // ...createNextConfig(__dirname, [
  //   ...nextConfig,
  // ]),
];

// .prettierrc.json
{
  "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
}

ESLint Configurations

Base ESLint Config

The shared ESLint flat config provides strict type-checking, import ordering, JSDoc, and code style rules for TypeScript projects.

import createConfig from "@hardlydifficult/ts-config/eslint";
import type { Linter } from "eslint";

const config: Linter.Config[] = createConfig("path/to/project/root");

Key Features:

• TypeScript strict type-checking via typescript-eslint
• Import ordering with eslint-plugin-import-x
• JSDoc enforcement on exported symbols via eslint-plugin-jsdoc
• Unused import removal via eslint-plugin-unused-imports
• Code style enforcement (e.g., prefer-const, no-var, curly: "all")

Ignores:

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

Next.js ESLint Config

For Next.js projects, combine the base config with Next-specific rules.

import createNextConfig from "@hardlydifficult/ts-config/eslint-next";
import type { Linter } from "eslint";
import nextConfig from "./next.config.js";

const config: Linter.Config[] = createNextConfig(__dirname, [
  ...(nextConfig as Linter.Config[]),
]);

Next-specific rules:

• Disables React scope rule (react/react-in-jsx-scope: "off")
• Disables prop-types (react/prop-types: "off")
• Enforces self-closing components for components and HTML
• Enforces consistent JSX boolean value style (never)
• Warns on array index keys
• Enforces JSX curly brace presence (props: "never", children: "never")

Prettier Configuration

Prettier code formatting configuration for TypeScript/JavaScript projects.

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

export default prettierConfig;

| Option | Value | |-----------------------------|--------------------------| | 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 |

TypeScript Configuration

Base tsconfig

Provides strict settings and modern ES2022 features for consistent builds across the project.

{
  "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
  }
}

Project tsconfig

Base TypeScript configuration for Node.js projects.

{
  "compilerOptions": {
    "target": "ES2022",
    "module": "Node16",
    "moduleResolution": "node16",
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "declaration": true,
    "declarationMap": true,
    "sourceMap": true,
    "esModuleInterop": true,
    "skipLibCheck": true
  },
  "include": ["src/**/*"]
}

API Reference

| Export | Type | Description | |------------------------|-------------------|-------------------------------------------------------| | eslint | function | Creates the shared ESLint config for TypeScript | | eslint-next | function | Creates ESLint config for Next.js projects | | prettier | object | Prettier configuration object | | tsconfig.base.json | string (path) | Base TypeScript configuration (copied to output dir) |