{
  "plugins": [
    ["proposal-class-properties", { "loose": true }],
    "external-helpers",
    "syntax-flow",
    "transform-parameters",
    "transform-block-scoping",
    "transform-spread",
    "transform-classes",
    "transform-destructuring",
    "transform-arrow-functions",
    "transform-for-of"
  ]
}