.eslintrc.js

// without TypeScript (not tested)
module.exports = {
  root: true,
  extends: [
    'airbnb',
    'airbnb/hooks',
    'plugin:import/errors',
    'plugin:import/warnings',
    'prettier',
    'prettier/react',
  ],
  env: {
    browser: true,
  },
  overrides: [
    {
      files: ['**/*.test.js', '**/*.test.jsx'],
      env: {
        jest: true,
      },
    },
  ],
  settings: {
    'import/ignore': ['node_modules'],
  },
};

ts.eslintrc.js

// with TypeScript (original)
module.exports = {
  root: true,
  extends: [
    'airbnb',
    'airbnb/hooks',
    'plugin:@typescript-eslint/recommended',
    'plugin:import/errors',
    'plugin:import/warnings',
    'plugin:import/typescript',
    'prettier',
    'prettier/react',
  ],
  env: {
    browser: true,
  },
  overrides: [
    {
      files: ['**/*.test.ts', '**/*.test.tsx'],
      env: {
        jest: true,
      },
    },
    {
      files: ['*.js'],
      rules: {
        // Allow `require()` in config files.
        '@typescript-eslint/no-var-requires': 'off',
      },
    },
  ],
  rules: {
    'import/extensions': [
      'error',
      'ignorePackages',
      {
        js: 'never',
        mjs: 'never',
        jsx: 'never',
        ts: 'never',
        tsx: 'never',
      },
    ],
    // Not needed with TypeScript
    'import/default': 'off',
    'import/named': 'off',
    'import/namespace': 'off',
    'import/no-unresolved': 'off',
    // Doesn't play well with Formik's Field.
    'jsx-a11y/label-has-associated-control': 'off',
    // TODO: Enable this with same config as in api
    '@typescript-eslint/explicit-function-return-type': 'off',
    'react/jsx-filename-extension': ['error', { extensions: ['.tsx'] }],
  },
  settings: {
    'import/ignore': ['node_modules'],
    'import/resolver': {
      typescript: {}, // this loads <rootdir>/tsconfig.json
    },
  },
};