I've been using Angular for a couple of years now, and one repeated pattern that occurs when I'm diving into the codebase is how quickly and easily it's to make application logic unreadable with the reactive extensions library, to be more specific, NgRx. While it offers a large set of tools for managing asynchronous data, arguably no other stream processing framework can provide. It creates a callback hell that makes most of the logic way too complicated to comprehend than it could be when using the imperative approach. I'm still thinking that it's too much overhead for most client-side applications, and this is the exact reason I'm not using it in my projects.