In this chapter, you learned what MVC is, and how to write an application that follows that pattern. You also know how to use a router to route requests to controllers, Twig to write templates, and Composer to manage your dependencies and autoloader. You were introduced to dependency injection, and you even built your own implementation, even though it is a very controversial topic with many different points of view.
In the next chapter, we will go through one of the most important parts needed when writing good code and good applications: unit testing your code to get quick feedback from it.