Let’s take a look at how Swift’s key paths work, and how they relate to functions — both in terms of what comes built into the language itself, and what kind of utilities that we can write ourselves to form some really nice convenience APIs.

Let’s take a look at the role that controllers play within the MVC design pattern, and how we can avoid some of the most common issues when working with them — particularly around how we can break up Massive View Controllers into smaller building blocks.