.eslintrc.js

module.exports = {
  parser: '@typescript-eslint/parser', // Specifies the ESLint parser
  plugins: ['@typescript-eslint'],
  extends: [
    'eslint:recommended',
    'plugin:@typescript-eslint/recommended',
    // Uses eslint-config-prettier to disable ESLint rules from @typescript-eslint/eslint-plugin that would conflict with prettier
    'prettier/@typescript-eslint',
    // Enables eslint-plugin-prettier and displays prettier errors as ESLint errors. Make sure this is always the last configuration in the extends array.
    'plugin:prettier/recommended',
    'plugin:jest/recommended',
  ],
  parserOptions: {
    ecmaVersion: 2018, // Allows for the parsing of modern ECMAScript features
    sourceType: 'module', // Allows for the use of imports
    project: './tsconfig.json',
  },
  rules: {
    // Place to specify ESLint rules. Can be used to overwrite rules specified from the extended configs
    // e.g. "@typescript-eslint/explicit-function-return-type": "off",
    'prettier/prettier': 'error',
    '@typescript-eslint/explicit-function-return-type': [ 'error',
      { allowExpressions: true,  },
    ],
  },
}