Overview of the improvements

Phew, we made it. How do you think we did? Do you think the improvements were worth the effort? Let's see.

To see how far we have come, we should first recap where we started.

In Chapter 4, Introduction to the ACME Registration Service, we had a small, simple, working service. It got the job done for our users, but it created many inconveniences for those of us that had to maintain and extend it.

Global singletons

One of the biggest pains was undoubtedly the use of global public singletons. At first glance, they seemed to make the code more concise, but they were actually making it much harder for us to test.

The use of init() functions to create variables meant that we either ...