In this chapter, you have learned what Agile code design is, the levels of code design, symptoms of bad design, and the levels of code design, as well as how to practice Agile code design.

You also have learned the SOLID design principles and the façade design pattern. After that, you learned about the two types of architecture design: layered architecture and hexagonal architecture.

In the next chapter, you're going to learn how to design the language between the frontend and the backend with the RESTful API.