.babelrc

{
  "env": {
    "development": {
      "presets": [
        ["@babel/env", {"targets": {"chrome": "69", "firefox": "62"}}],
        "@babel/react"
      ],
      "plugins": [
        ["@babel/plugin-proposal-decorators", {"legacy": true}],
        "@babel/proposal-object-rest-spread",
        "@babel/plugin-proposal-class-properties"
      ]
    },
    "backend": {
      "presets": [
        ["@babel/env", {"targets": {"node": "10"}}]
      ],
      "plugins": [
        ["@babel/plugin-proposal-decorators", {"legacy": true}],
        "@babel/proposal-object-rest-spread",
        "@babel/plugin-proposal-class-properties"
      ]
    },
    "test": {
      "presets": [
        ["@babel/env", {"targets": {"node": "10"}}]
      ],
      "plugins": [
        ["@babel/plugin-proposal-decorators", {"legacy": true}],
        "@babel/proposal-object-rest-spread",
        "@babel/plugin-proposal-class-properties"
      ]
    }
  }
}