Start New Next.js Project Notes

Please read the Getting Started guide, it is really good.

Create a new app

Run yarn create next-app and follow the instructions.

Move code to src folder

I like to keep all source code in one folder. Next.js supports src folder by default. Create src folder and move pages and styles there.

Add Typescript

Next.js provides an integrated TypeScript experience out of the box.

Create TypeScript config file:

touch tsconfig.json

Next.js will automatically configure this file with default values.

Install dependencies:

yarn add --dev typescript @types/react @types/node

Run dev server with yarn dev. Next.js will generate tsconfig.json file for us.

Change strict inside compilerOptions to true if you want the real TypeScript experience. This option will prevent you from not specifying types and from using any.

Add absolute imports

Add baseUrl parameter to the tsconfig.json config compilerOptions:

{
  "compilerOptions": {
    ...
    "baseUrl": "."
    ...
  }
}

Restart dev server with yarn dev. Now we should be able to import with an absolute path from the project's root.

import 'src/styles/globals.css'

Add ESLint

yarn add --dev eslint @typescript-eslint/parser  @typescript-eslint/eslint-plugin eslint-plugin-react eslint-plugin-react-hooks eslint-plugin-jsx-a11y

• eslint is the main ESLint package
• @typescript-eslint/parser will allow ESLint to parse TypeScript files
• @typescript-eslint/eslint-plugin will add TypeScript specific lint rules
• eslint-plugin-react will add React specific lint rules
• eslint-plugin-react-hooks will add React Hooks rules
• eslint-plugin-jsx-a11y will add accessibility related rules

Create a .eslintrc.js config file:

module.exports = {
  root: true,
  env: {
    node: true,
    es6: true,
  },
  parserOptions: { ecmaVersion: 2020 },
  ignorePatterns: ['node_modules/*', '.next/*', '.out/*'],
  extends: ['eslint:recommended'],
  overrides: [
    // This configuration will apply only to TypeScript files
    {
      files: ['**/*.ts', '**/*.tsx'],
      parser: '@typescript-eslint/parser',
      settings: { react: { version: 'detect' } },
      env: {
        browser: true,
        node: true,
        es6: true,
      },
      extends: [
        'eslint:recommended',
        'plugin:@typescript-eslint/recommended',
        'plugin:react/recommended',
        'plugin:react-hooks/recommended',
        'plugin:jsx-a11y/recommended',
      ],
      rules: {
        'react/prop-types': 'off',

        // No need to import React when using Next.js
        'react/react-in-jsx-scope': 'off',

        // This rule is not compatible with Next.js's <Link /> components
        'jsx-a11y/anchor-is-valid': 'off',

        // Why would you want unused vars?
        '@typescript-eslint/no-unused-vars': ['error'],

        // I suggest this setting for requiring return types on functions only where useful
        '@typescript-eslint/explicit-function-return-type': [
          'warn',
          {
            allowExpressions: true,
            allowConciseArrowFunctionExpressionsStartingWithVoid: true,
          }
        ]
      }
    }
  ]
}

Add Prettier

yarn add --dev prettier eslint-plugin-prettier eslint-config-prettier

Create a .prettierrc.js config file:

module.exports = {
  semi: false,
  trailingComma: 'none',
  singleQuote: true,
  printWidth: 100,
  tabWidth: 2,
  useTabs: false,
}

Add prettier to ESLint config:

module.exports = {
  // ...
  overrides: [
    {
      // ...
      extends: [
        // ...
        'plugin:prettier/recommended', // Prettier plugin
      ],
      rules: {
        // ...
        'prettier/prettier': ['error', {}, { usePrettierrc: true }], // Includes .prettierrc.js rules
      },
    },
  ],
}

Add Husky

Add lint script to package.json:

{
  "scripts": {
    ...
    "lint": "tsc --noEmit && eslint 'src/**/*.{js,jsx,ts,tsx}' --fix"
  }
  ...
}

Add lint-staged config to package.json:

  "lint-staged": {
    "*.{js,jsx,ts,tsx}": [
      "yarn lint"
    ]
  },

Install Husky and Lint-staged:

yarn add husky lint-staged -D

Add Husky pre-commit hook:

yarn husky install
yarn husky add .husky/pre-commit "yarn lint-staged"

Start development server yarn dev and enjoy coding! 🎉

P.S. Please checkout the repo if you stuck. 🙌🏻

Credits

Photo by Gia Oris on Unsplash