[WkndTriathlete]

I find the big problem with async is the libraries, not necessarily the async piece itself. I looked at Webflux (Project Reactor)/RxJava/etc. years ago and discovered that the composable async components unexpectedly maintain state, and that's really the piece that makes it hard to reason about.

I've since switched over to Scala + cats-effect. I found that to be a huge learning curve, but the payoff for me has been library support for easy-to-use and easy-to-understand concurrent and asynchronous programming. I cannot recommend it enough.