.babelrc

{
  "plugins": [
    "@babel/plugin-syntax-dynamic-import",
    ["@babel/plugin-proposal-decorators", { "legacy": true }],
    "@babel/plugin-proposal-class-properties",
    "@babel/plugin-proposal-object-rest-spread",
    ["@babel/plugin-transform-runtime", { "corejs": 2 }]
  ],
  "presets": [
    [
      "@babel/preset-env",
      {
        "useBuiltIns": "usage",
        "targets": {
          "browsers": [
            "> 0.25%",
            "IE 9"
          ]
        },
        "modules": false,
        "loose": true
      }
    ],
    "@babel/preset-react",
    "@babel/preset-flow"
  ],
  "env": {
    "development": {
      "plugins": [
        "react-hot-loader/babel"
      ]
    },
    "test": {
      "plugins": [
        "@babel/plugin-transform-modules-commonjs",
        "dynamic-import-node"
      ]
    }
  }
}