For skipping the login prompt, I’m using the setting

services.displayManager.autoLogin = {
  enable = true;
  user = "your-username";
};

I would guess that works with most display managers.

I think I just set flex-launcher to auto start in my KDE settings (not through nix).

But yeah, the learning curve for nix is pretty steep, but it’s not too bad once you get past the kinda weird syntax. I followed https://grahamc.com/blog/erase-your-darlings/ + the official installation docs for my install. It’ll definitely take some trial and error when writing your config, but the nice thing is you can make all kinds of mistakes without breaking your system.

Yeah, I’m surprised too by how little there is for htpc use cases. And I’m bummed by how little development plasma bigscreen has seen.

Oh, honestly most of the software I’m using on it isn’t configured through nix. I’m sure I could go a bit further configuring Kodi with it, but the other things like Steam and Firefox wouldn’t really benefit.

If I were you, I’d just focus first on getting the base system setup and software installed. Then once you have the software how you like, start porting configuration over to your nix config file(s). That’s one of the nice things about NixOS; there’s no rush to get everything in a single config file, but you can opt in when it makes sense.

I don’t know about hottest, but on my little HTPC I’m running NixOS with KDE (mainly for KDE Connect, but it’s nice to have a DE of some sort when things crash/break).

I set up flex launcher to auto start and added menu options for Kodi, Firefox, and Steam.

I used to run LibreElec. It was mostly fine, but the Kodi YouTube plugin breaks just often enough that I wanted to have a web browser as backup. Also, I eventually wanted to play/stream games to it.