Create hello world React app with hot module replacement

src/app.js

@@ -0,0 +1,11 @@
+import React from 'react';
+
+export default class Site extends React.Component {
+    render() {
+        return (
+            <div>
+                Hello React!
+            </div>
+       );
+    }
+}

src/index.js

@@ -0,0 +1,22 @@
+import React from 'react';
+import ReactDOM from 'react-dom';
+import 'react-hot-loader/patch';
+import { AppContainer } from 'react-hot-loader';
+
+import App from './app';
+
+
+const render = Component => {
+    ReactDOM.render(
+        <AppContainer>
+            <Component />
+        </AppContainer>,
+        document.getElementById('root')
+    )
+}
+
+render(App)
+
+if (module.hot) {
+    module.hot.accept('./app', () => { render(App) })
+}