.eslintrc.json

{
  "env": {
    "browser": true,
    "es6": true,
    "node": true,
    "mocha": true,
    "mongo": true,
    "jest": true
  },
  "extends": ["eslint:recommended"],
  "parserOptions": {
    "ecmaVersion": 2018,
    "sourceType": "module",
    "ecmaFeatures": {
      "jsx": true
    }
  },
  "ecmaFeatures": {
    "arrowFunctions": true,
    "binaryLiterals": true,
    "blockBindings": true,
    "classes": true,
    "defaultParams": true,
    "destructuring": true,
    "forOf": true,
    "generators": true,
    "modules": true,
    "objectLiteralComputedProperties": true,
    "objectLiteralDuplicateProperties": true,
    "objectLiteralShorthandMethods": true,
    "objectLiteralShorthandProperties": true,
    "octalLiterals": true,
    "regexUFlag": true,
    "regexYFlag": true,
    "spread": true,
    "superInFunctions": true,
    "templateStrings": true,
    "unicodeCodePointEscapes": true,
    "globalReturn": true
  },
  "rules": {
    "indent":["error",2,{"SwitchCase":1}],
    "linebreak-style":["error","unix"],
    "quotes":["error","single"],
    "semi":["error","always"],
    "no-console":["warn"],
    "no-unused-vars":["warn"],
    "strict":["off","safe"],
    "no-eval":["error"],
    "eqeqeq":["error"],
    "array-bracket-spacing": ["error", "never"],
    "object-curly-spacing": ["error", "always"],
    "space-before-function-paren": ["error", {
      "anonymous": "never",
      "named": "never",
      "asyncArrow": "always"
    }],
    "space-before-blocks": "error",
    "no-var": "error",
    "space-in-parens": ["error", "never"],
    "no-trailing-spaces": "error",
    "no-multiple-empty-lines": "error",
    "keyword-spacing": "error",
    "comma-spacing": "error"
  }
}