{
  "env": {
    "es5": {
      "presets": [
        "es2015"
      ]
    },
    "es6": {
      "presets": [
        "es2016",
        "stage-3"
      ]
    },
    "test": {
      "presets": [
        "es2015"
      ],
      "plugins": ["istanbul"]
    }
  },
  "plugins": [
    ["transform-class-properties", { "spec": true }]
  ]
}