.eslintrc.json

{
    "env": {
        "node": true,
        "mocha": true,
        "es6": true
    },
    "parserOptions": {
        "ecmaVersion": 6,
        "ecmaFeatures": {
            "impliedStrict": true // enable global strict mode
        }
    },
    "extends": "eslint:recommended",
    "rules": {
        "quotes": [
            "error",
            "single"
        ],
        "semi": [
            "error",
            "always"
        ],
        "no-console": "warn",
        "eqeqeq": "error",
        "no-var": "warn"
    }
}