.babelrc

{
  "presets": [
    [
      "razzle/babel",
      {
        "preset-env": {
          "modules": false, // don't convert modules into CommonJS
          "useBuiltIns": "usage", // use polyfill when needed
          "corejs": 3
        },
        "class-properties": {
          "loose": false
        }
      }
    ],
    "@babel/preset-react"  // Transpile React components to JavaScript
  ],
  "plugins": [
    "@babel/plugin-proposal-export-default-from",
    "@babel/plugin-syntax-dynamic-import",
    "@babel/plugin-syntax-import-meta",
    "@babel/plugin-proposal-json-strings",
    ["@babel/plugin-proposal-decorators", { "legacy": true }],
    "@babel/plugin-proposal-export-namespace-from",
    "@babel/plugin-proposal-throw-expressions",
  ],
  "env": {
    "test": {
      "plugins": [
        "dynamic-import-node",
        "@babel/plugin-transform-react-jsx",
        "@babel/plugin-transform-modules-commonjs",
      ]
    }
  }
}