I've been curious about NixOS for quite some time. Reading about it I couldn't see how the config sharing capabilities, setup, or rollabck would be better than Arch and sharing the list of installed packages, using downgrade or chroot.
So I decided to run NixOS in a VM and I'm still confused. An advantage I can see for NixOS is its better use of cores and parallel processing for packages install.
It's clear that I'm missing something so please help me understand what it is.
Edit: Thank you to everyone in this great community! It's always so nice to have a constructive and sane discussion.
After reading so many comments, they all confirm what I've read before and I may realize that my real problem is already having a stable system and no need for the great NixOS options that are very neat but would not benefit my specific and simplistic needs.
That being said I can't refrain myself from being curious and will continue testing NixOS.
The need for only 2 config files is the top of the iceberg but hiding more complex configuration to rely on. Not that I really have too much spare time but I do enjoy learning and tweaking NixOS. With its current development state, things are changing a lot so it can keep me busy for months. That's probably what I was mostly looking for: another toy to play with.
Along my journey I will learn a lot about NixOS and may find a feature that will motivate my switch to it. Thanks again for all your precious feedback!
I'll also take this opportunity to share the best help I've found so far to start with NixOS: https://github.com/MatthiasBenaets/nixos-config And his 3 hours (!) video: https://m.youtube.com/watch?v=AGVXJ-TIv3Y
I think if you have no answer, it could be that NixOS doesn't solve any problem for you. In effect, it's not better. Don't buy into social media hype. It's just a tool like any other.
You're spot on and that's what this discussion helped me figure out: I have no problem. I knew that but I also thought that NixOS would bring something new to improve my Linux usage. So far I still see such improvements for servers or deployment on several machines but not for a single user with standard needs (and this statement may be wrong and due to my limited experience with NixOS).
But NixOS approach is quite different from others and I feel like I may discover something of interest to me once I learn more about it. Also, just for the sake of learning and discovering, I will continue experimenting with it for a while.
In short, Nix reduces the setup time, both for your system and for your projects. If you find yourself spending a while setting stuff up (for example, after a reinstall; or maybe you want to run your project on another PC and need to install the right dependencies), Nix will help. Otherwise, if your desktop is vanilla Fedora or whatever and you don't do much programming (or you don't have any dependency management problems), Nix probably isn't for you.