CODE EXAMPLE FOR JAVASCRIPT

react port

// Ubuntu / CentOS / RHEL / MacOS environment:

...
  "scripts": {
    "start": "PORT=8000 react-app-rewired start",
    "build": "react-app-rewired build",
    "test": "react-app-rewired test --env=jsdom",
    "eject": "react-app-rewired eject"
  }
...