If you're a Python programmer looking to learn Go, you'll be happy to know that Go has a similar concept to classes called "structs". Structs are similar to classes in that they allow you to define a custom data type with its own fields and methods.

If you are following this series from start, you know that we can already create user from our API. But we have our tests failing right now, which is kind of smelly. In this post, we takle with the problem in our hand and discuss some methods we can do it with. One of them is dependency injection.