Put webpack into development mode

README.md

@@ -26,6 +26,12 @@ Open `index.html` in the browser, and you should find yourself faced with Conway
 
 ## Install loaders for Vue or React
 
+Before we go any further, let's put webpack into development mode. In `webpack.config.js`, at the top of `module.exports`, set:
+
+```js
+  mode: 'development',
+```
+
 If you're using Vue, install the modules for vue:
 
 ```sh
@@ -43,7 +49,6 @@ You'll also need to alter `webpack.config.js` to load the version of Vue that in
   },
 ```
 
-
 If you're using React, though, you'll need to install the modules for react:
 
 ```sh