In this chapter, we talked about compiling and preparing our application for a production environment. This step has become quite important since version 4. Using Sencha CMD and also configuring JSON or XML files to build a project can sometimes be an overwhelming situation, but don't panic! Check out the documentation of Sencha and Apache.
Take a look at the JSON and XML files in examples, mainly in the kitchen sink example. This example has very complex JSON and XML files for building the application, which can give you some pointers to new ideas on how to work with it.
Also, remember that there's no reason to be afraid of testing and playing with the configurations. It's all part of learning and knowing how to use Sencha Ext JS.