Setting Up Linting and Formatting

No TypeScript setup is complete without proper linting. Here’s a solid ESLint configuration for React 19 + TypeScript:

npm install -D eslint @typescript-eslint/parser @typescript-eslint/eslint-plugin
npm install -D eslint-plugin-react eslint-plugin-react-hooks
npm install -D prettier eslint-config-prettier

Create .eslintrc.json:

{
  "extends": [
    "eslint:recommended",
    "@typescript-eslint/recommended",
    "plugin:react/recommended",
    "plugin:react-hooks/recommended",
    "prettier"
  ],
  "parser": "@typescript-eslint/parser",
  "plugins": ["@typescript-eslint", "react"],
  "rules": {
    "react/react-in-jsx-scope": "off",
    "@typescript-eslint/no-unused-vars": ["error", { "argsIgnorePattern": "^_" }],
    "@typescript-eslint/explicit-function-return-type": "off",
    "@typescript-eslint/explicit-module-boundary-types": "off",
    "@typescript-eslint/no-explicit-any": "warn"
  },
  "settings": {
    "react": {
      "version": "detect"
    }
  }
}

And .prettierrc.json:

{
  "semi": true,
  "trailingComma": "es5",
  "singleQuote": true,
  "printWidth": 80,
  "tabWidth": 2
}