I'm a huge fan of typed functional programming. I've also been working with JavaScript and Node.js for a lot longer than I've been working with languages like Haskell. So when we were building out the server for Ellie I wanted to use what I've learned studying functional programming while sticking with a language and platform familiar to web developers. A huge theme of my programming practice so far has been understanding how to represent effects like database calls and network requests in a way that is still testable.