Callback Hell is a problem affecting developers of all stripes trying to write asynchronous code that’s easy to follow. iOS developers don’t yet have much in the way of built-in options to reduce callback hell, but there are several libraries which purport to help. In this session, you’ll get a look at what problems are being solved by RxSwift and PromiseKit, as well as a look at an intriguing functional technique to avoid callback hell without libraries. And you’ll learn more about how to answer the question: Which of these hammers is the most appropriate for my particular nail?