.babelrc

{
    "env": {
        "test": {
            "presets": [
                [
                    "env",
                    {
                        "targets": {
                            "node": "current"
                        }
                    }
                ]
            ]
        }
    },
    "plugins": [
        [
            "transform-runtime",
            {
                "helpers": false,
                "polyfill": false,
                "regenerator": true,
                "moduleName": "babel-runtime"
            }
        ]
    ],
    "presets": [
        [
            "env",
            {
                "debug": false,
                "targets": {
                    "node": "current",
                    "browsers": [
                        "> 1%",
                        "last 2 versions",
                        "ie >= 9"
                    ]
                },
                "useBuiltIns": true,
                "modules": false
            }
        ]
    ]
}