Always use the Magento architecture

As seen in Chapter 3 , Magento 2 Theme Layout, the Magento system uses MVC concepts. This standard provides the segmentation of different system components, aiming at better use of its resources and providing modularity in developing solutions and customizing architecture.

For all development that is performed in the system, it is strongly recommended you use the architecture aiming for standard maintenance to share your solutions between different instances and projects.

During the development of the Bookstore theme, we used the app/design/frontend/Packt/bookstore directory, inheriting the Blank and Luma theme features but not changing them directly. For the development of the modules, we used the app/code/Packt directory but without directly changing the modules that supported the development of the new module, such as the product catalog module used to power the operation of jCarousel.

These techniques reinforce another good practice: you should not...