I see what you mean, interesting. Didn’t really look at NixOS as a server os. I personally prefer using multiple compose files (in the process of migrating to k8s). I share resources too, like in your example, I just point to the existing DB instance, not create a new one for each new service.

May I ask what you mean by NixOS support? There’s a docker compose you could use in their repo…

I believe R-- stands for Readarr and G–R-- stands for GoodReads.