.babelrc

{
  // An important note is that babelrc does not merge presets or plugins
  "presets": [
    ["@babel/preset-env",
      {
        "targets": "> 0.25%, not dead"
      }
    ],
    "@babel/preset-react",
    "@babel/preset-flow"
  ],
  "plugins": [
    // "babel-plugin-emotion", // yarn add emotion react-emotion && yarn add babel-plugin-emotion --dev --exact
    // ["babel-plugin-styled-components", { "displayName": true }] // yarn add styled-components && yarn add babel-plugin-emotion --dev --exact
  ],
  "env": {
    "production": {
      "plugins": [
        "lodash"
      ]
    },
    "development": {
      "plugins": [
        "react-hot-loader/babel"
      ]
    },
    "test": {
      "presets": [
        [
          "@babel/env",
          {
            "targets": {
                "node": "current"
            }
          }
        ],
        "@babel/preset-react",
        "@babel/preset-flow"
      ],
      "compact": false
    }
  }
}