Now that we've seen how the principle functional approach to the implementation of the microservice works, let's change our technological stack and implement the same shop with Akka-HTTP and Akka Persistence. The flow of the discussion for this example will be similar to the one we had about the functional approach—we will start with looking at the way to persist the state of the service and the configuration needed for that. We'll then address the task of actually persisting the data and providing access to it via the HTTP service. As before, we'll conclude our journey by testing the implementation we'll come up with.