title: Using babel-polyfill in production entry file
body: <p>I'm using babel to transpile ES7 js code, and everything works like a charm in dev/staging. Inside the application, I heavily rely on <em>async/await</em> features of ES7. My entry file looks like this: </p>
  
  <pre><code>'use strict';
  require("babel-polyfill");
  require("babel-core/register");
  module.exports = require('./app/server').default();
  </code></pre>
  
  <p>I'm not sure whether it is necessary to keep <em>babel-polyfill</em> and <em>babel-core/register</em> modules for the production environment since I transpile everything using babel-cli before deployment. I assume it must correctly work even if I remove those and make the entry file look something like this:</p>
  
  <pre><code>import server from './app/server';
  server();
  </code></pre>
  
  <p>However, if do this I got next exception while starting the application: </p>
  
  <pre><code>ReferenceError: regeneratorRuntime is not defined
      at C:\Users\Username\Documents\some-service\lib\app\repositories\someRepository.js:18:32
      at Object.&lt;anonymous&gt; (C:\Users\Username\Documents\some-service\lib\app\repositories\someRepository.js:40:2)
      at Module._compile (module.js:460:26)
      at Object.Module._extensions..js (module.js:478:10)
      at Module.load (module.js:355:32)
      at Function.Module._load (module.js:310:12)
      at Module.require (module.js:365:17)
      at require (module.js:384:17)
      at Object.&lt;anonymous&gt; (C:\Users\Username\Documents\some-service\lib\app\controllers\someController.js:15:27)
      at Module._compile (module.js:460:26)
      at Object.Module._extensions..js (module.js:478:10)
      at Module.load (module.js:355:32)
      at Function.Module._load (module.js:310:12)
      at Module.require (module.js:365:17)
      at require (module.js:384:17)
      at Object.&lt;anonymous&gt; (C:\Users\Username\Documents\some-service\lib\app\server.js:15:26)
      at Module._compile (module.js:460:26)
      at Object.Module._extensions..js (module.js:478:10)
      at Module.load (module.js:355:32)
      at Function.Module._load (module.js:310:12)
      at Module.require (module.js:365:17)
      at require (module.js:384:17)
  </code></pre>
  
  <p>Is that normal to reference <em>babel-polyfill</em> and <em>babel-core/register</em> packages in the production environment? </p>