.babelrc

{
    "env": {
        "commonjs": {
            "presets": [
                [
                    "es2015",
                    {
                        "loose": true
                    }
                ]
            ],
            "plugins": [
                [
                    "transform-es2015-modules-commonjs",
                    {
                        "loose": true
                    }
                ]
            ],
        },
        "es": {
            "plugins": [
                [
                    "transform-es2015-classes",
                    {
                        "loose": true
                    }
                ],
                "transform-es2015-arrow-functions",
                "transform-es2015-block-scoping",
                "transform-es2015-destructuring",
                "transform-es2015-typeof-symbol",
                "transform-es2015-template-literals",
                [
                    "transform-es2015-for-of",
                    {
                        "loose": true
                    }
                ],
                "transform-es2015-parameters",
            ]
        }
    }
}