Chapter 4: Creating Adapters to Interact with the Outside World

There is a moment in software development when we need to decide which technologies will be supported by a system. We've been discussing in the previous chapters how technological choices should not be the primary driver for developing hexagonal applications. In fact, the applications based on such architecture present a high degree of changeability, enabling with as little friction as possible a system to be integrated with different technologies. This is due to how the hexagonal architecture helps to establish a clear frontier between which part of the code is related to business and which is related to technology.

In this chapter, we're going to explore the hexagonal approach to establish this frontier. We'll learn about the role adapters play when we need to set up technologies or protocols to enable a hexagonal application to communicate with the outside world.

We'll learn about the following...