I've been 100% on NixOS on many years, but it's Debian that really drove this project.

They're still a pragmatic choice for many usecases.

In the end, Nix is just a thin veneer on this stuff.

Given how many quick & dirty sed patching or exec commands I've seen in the few nix package/modules I've read, I would not exactly bet my life on it being completely idempotent & reproducible.

bootcrew have bootc Containerfiles for Debian, Ubuntu, Arch, and openSUSE:

https://github.com/bootcrew/mono