.eslintrc.js

module.exports = {
  parser: 'babel-eslint',
  extends: 'eslint:recommended',
  globals: {
    Promise: true,
    Buffer: true,
    fetch: true,
    require: true,
    process: true,
    module: true,
    setTimeout: true,
    __dirname: true,
  },
  rules: {
    'space-before-function-paren': ['error', 'never'],
    semi: ['error', 'never'],
    'no-underscore-dangle': 0,
    // allow debugger during development
    'no-debugger': process.env.NODE_ENV === 'production' ? 2 : 0,
    // trailing comma
    'comma-dangle': ['error', 'always-multiline'],
    quotes: ['error', 'single', { 'avoidEscape': true, 'allowTemplateLiterals': true }],
  },
}