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I’m trying to deploy my app but when I run this command: npm run build I get some error messages.

Versions: Node: v7.4.0 NPM: 4.0.5 React-Boilerplate: 3.4.0

[Jarinel]

Looks like it’s a bug in babel-plugin-transform-react-constant-elements. Had the same issue and removing it from env plugins helped me

[danielrob]

Apologies to comment on a close issue, but for those who end up here from google, my gotcha here was I had added code outside of app directory, not realising that the react-boilperplate package.json configures babel, and configures it only the app directory.

Updating to:

  "babel": {
     "presets": [ ... ]
    "env": {
      "production": {
        "only": [
          "app1",
          "app2",
          "common"
        ],
...

Solved my problem