> Once we have the state machine figured out, we can build whatever arbitrary UI we want on top of it. You can. It's probably still better to use a comfortable

> Once we have the state machine figured out, we can build whatever arbitrary UI we want on top of it. You can. It's probably still better to use a comfortable UI library to help, and if you're doing your app state transitions in a central place, pick a view library that works well with that pattern (React, its siblings, or Vue for example). In a toy app, I recently tried updating some DOM using the unidirectional data flow model, but without a UI library. It was horrid. The DOM really fights you in this regard: it's pure OO and stateful itself so you're better off using a library to tear down and rebuild your DOM for you.