Fix hmr

src/index.js

@@ -1,20 +1,26 @@
 import 'babel-polyfill';
 
-import ReactDOM from 'react-dom';
-import ReactDOMServer from 'react-dom/server';
-
-import App from 'App';
+// NOTE: we are requiring with require(), to enable dynamic dependencies
+// depending on ENV, where App is running in.
+// This allows us better support of hmr and reduces bundle size
 
 /* global process: false */
+// eslint-disable-next-line no-negated-condition
 if (process.env.NODE_ENV !== 'production') {
+    const ReactDOM = require('react-dom');
     const DevApp = require('devTools').default;
 
     ReactDOM.render(
         <DevApp />,
         document.getElementById('app')
     );
-}
+} else {
+    const ReactDOMServer = require('react-dom/server');
+    const App = require('App').default;
 
-export default function(props) {
+    module.exports = {
+        default(props) {
             return ReactDOMServer.renderToStaticMarkup(<App {...props} />);
         }
+    };
+}