> The problem is, documentation is sparse to non-existant, error messages are poor and often far from the actual problem, and it makes use of concept that lots of people are not familiar with (like lazy evaluation) without ever explaining them, resulting in surprising semantics.

I used NixOS and Home-Manager to run my entire system and home directory for a couple weeks earlier this year. The lack of clear documentation made me leave. Most of the time to find relevant information I'd have to go in some chat room since often the "official" documentation would be outdated. If the documentation was better I'd probably still be on it.