Why everyone is switching to NixOS ?

This very much. I used to have lots of unchecked config and state files everywhere on Arch. Now everything is checked in and wiped on boot so if something breaks after a reboot i know what broke.

Like how the opengl rendering did due to nixpkgs version differences

Oh boy my two cents time!

I love the concept of NixOS. A fully declarative , reproduceable system from a single config repo! Sounds theoretically like it would be my kind of thing.

Sure, theoretically, I could have a fully reproduceable system. The time spent declaring that fully reproduceable system though... I remember the first time I was trying to get my usual disk setup of, a luks encrypted btrfs partition with multi-factor enabled decryption/authentication.

On a normal install it would take like a day at worse to install your distro. My first attempt with NixOS took me almost 4 days of screwing around in configs. 2 of those days were probably cumulatively spent waiting for the config option list of the nixos manual to search for text. And the number of redundant config options which all do the same thing! Or, are supposed to all do the same thing but in actuality, only one of them does the thing they are supposed to.

I really want to love NixOS but it always ends up feeling like an exercise in my patience and time to do even the simplest of things. As such I find myself asking the question of, am I going to spend so much time reinstalling my distro that it's ever worth this initial investment?

Anyways, rant over. I actually have been debating switching back over for another try again myself I just have some very frustrating memories of my first attempts with the distro.

Note that there's both the rolling unstable channel and a bi-annual stable release channel.

Important to note that NixOS has both a rolling release and point release version.

The configuration stuff seems great. I guess it reduce the struggle of porting a full config from one pc to another right ?

Are you still using it and happy with it? I've been increasingly using single purpose dev VMs in a server, and a declarative configuration system would make the process of spinning them up faster and more robust. My current shell script system is clunky, and I've been looking at Ansible.

Indeed, why would I switch, already have been running NixOS for 10+ years.

I'll edit. That was clearly a stretch

I use Arch NixOS BTW.

Well, Nix has a very liberal definition of a "package". Your web browser, its wrapper script, a service file, a config file; those are all technically "packages" (or "derivation" as Nix calls them).

Doesn't it have a garbage collector like guix does (guix gc), which cleans up everything in the store that isn't needed anymore?

Do you run the gnu guix distro or just use the package manager? Because iirc it uses only free software, even for drivers. So I imagine it is not that easy to find compatible hardware.

That is the main reason I can't use my laptop with linux. It has a 3060 in it. I work as a dev and need to use 2-3 external displays with my laptop. The driver combined with x or wayland is atrocious, I tried 20 distros and I can't get it to work. The saddest thing is that none of the tech is exotic in any way. It's just HDMIs and AOC 24 inch monitors...

It's kind of funny because I'd put NixOS on a complete newbies computer for sure, and recommend it to an expert... But I'm less sure if I'd tell a random mid-intermediate Linux user to switch.

Like if Grandma wants Linux on their computer to do some internet browsing for some reason... I'd absolutely put NixOS on it because it's easy to manage the system for them... But somebody who is a little familiar with Linux already might be more confused about the differences. It's kind of the ultimate beginner distro and the ultimate power-user distro, but a bit awkward between those extremes, haha.

It's true that it can be a powerful distro but I've also heard from some users that the advanced-level documentation is lacking and only limited to forums and source code. I think maybe if the documentation was more thorough I would try nixos.

you have to have a lot of linux/programming knowledge to do even the simplest things like installing/updating your software

So, pretty much like any other distro

I think I will give it a try on a server first, I don’t have a playbook or script for a reproducible set up (yet), so I may as well use Nix to see if it’s worth the hype

The nice thing about nix and guix is that they're package managers, and so you get most of the benefits even if you're using a different OS.

I'm currently transitioning from Doom Emacs to my own config that's using guix. So far I've got a single manifest that contains all of the Emacs and Linux packages that are needed to run the config.

The guix part is really simple, but it allows me to reproduce my config on any Linux distro by cloning a repo and running a guix one liner. A different one liner can run it in a containerised environment. Also, I can roll back to any previous time I've updated something through that manifest, or pin a specific version of a package.

And that's just scratching the surface of what you can do.

It is an immutable distro, altough it isn't image-based like Fedora's rpm-ostree.

NixOS basically replaces Ansible because the Nix package manager achieves the same goals already (configuration, deployment, ...).

But I agree, the work necessary to put into this non-standard distro makes it hard to recommend for a casual user.

I like using btrfs with Arch because of the snapshots. If an update breaks something I can just boot into a snapshot from grub keep using my PC and solve the problem later. It's very useful... yes... very... you should try it... come... try btrfs... it's warm and cozy... INSTALL IT!

NixOS has benefits not just for developers, altough being familiar with programming is helpful.

For me the main benefit of NixOS is being able to keep multiple systems in sync. For that I have 3 config files, the first containing all general config and packages I want to have installed. The other two are for my laptop and pc respectively, which allows me to make system-specific changes. E.g. tlp is only enabled and configured on my laptop.

And NixOS isn't just rolling release, it also has bi-annual stable releases, which is great for servers.

Rollbacks are also awesome, altough I used btrfs snapshots a few years back with Arch for a similar result. With a bit of setup they are bootable from grub.

The features themselves are very useful for basically any user. Whether they are worth the non-standardness and issues that come with it is another question.

Solution without a problem. A cool solution but yeah.

Thanks for this, it was definitely a nice overview. Not the first time I'd heard of NixOS, but I do seem to be seeing more frequent and more substantial discussions of it.

What I'm getting from all this, is that it looks to be a great way to set up reproducible desktop environments. And servers too, I suppose.

What I'm not getting from this: a compelling reason to switch from established players like RHEL and Ubuntu in combination with cloud-init and Terraform and the likes of Chef/Puppet/Ansible/Salt to spin up a cluster in the cloud, reconfigure, tear down, etc.

In case anyone is misreading me: this is not a dig at NixOS. It definitely looks interesting. Like, to the point that I'll at least spin up a VM on my Manjaro laptop and see whether I should perhaps consider wiping and reinstalling with NixOS. The "configuration through code" is extremely appealing here.

My concern here is corporate inertia. And before anyone gets gets ready to launch a diatribe about how corporations don't decide what the best tech is, I will agree with you. I've been around a while, and excitedly watched as Unix ramped up and displaced platforms like VAX/VMS and AOS/VS, using smaller and faster hardware. Then along came Linux and the battle for which distros would dominate.

As for configuration through code, I've been keeping a keen eye on things (tinkering when it's been possible to do so) since the days of cfengine and Jumpstart. I used to share this site with anyone that would listen to me; it's dated now, but the underlying principles are (were?) solid: http://infrastructures.org/

So for now, I think I'll have to limit my professional NixOS usage to tinkering and potentially useful side projects. For personal usage? Yeah, it might become my daily driver, but I need to find the time to tinker.

I will say that I'm presently involved in an effort to test something out that has my company's product available using rpm-tree. Not my decision, this is all being driven by a customer that has a lot of clout; they really, really want to use rpm-tree. It's proven to be a bit onerous at times.

What this NixOS discussion has managed to do for me is to have me wondering whether a NixOS approach would have worked out better; my sense is that yeah, maybe it would have. But my feelings here might simply be the result of "woo, shiny new object", which has definitely colored my opinions of things in my career of 35 years. Something that I've had to restrain my excitement over, pending corporate sanity checks.

Having the option to have multiple versions of a dependency without needing to have duplicates of the same version alá flatpak seems like it should've been a no-brainer on any linux distro.
With that said I'm very comfortable with my current system, so definitely not until I get majorly fucked by my life-choices
Definitely sounds like a competent player in comparison to most distros though.

And I feel like the terminal isn't as big a barrier as everyone makes it out to be (part of why I say that is because I think the entire concept of "beginner friendly distros" only makes the terminal seem more impenetrable through that wording)

All-in-one config is definitely something I would've hoped Arch had as well, and as a bonus I would love a system that kept all things related to the user in /home (I'm not completely sure Nix does but I may as well throw that in) (homed does not do that as it still has entities outside of /home that you better back up, in fact you'll risk being locked out of your user if you don't)

I've made the jump twice, and jumped back twice.

Conda and any other reproducible computing library that relies on LHS Linux filesystem just doesn't work on it (okay it does, but more as an obstacle)

I'm okay with having nix the package manager on my default arch system though, since it is incredibly useful for cross compiling, and it let's me modify my system however I want.

To get it out of the way first: There are no financial issues. There are more than enough funds to continue operations as they are for a sufficiently long time.

What is actually happening is that a long time sponsor has indicated that they (understandably) no longer want to foot the huge bill of hosting the entire archive of binary caches ($9000/mo). Finding a more sustainable setup is what the community is currently concerned with.
There is no risk of operations shutting down any time soon, the NixOS foundation has funds set aside to continue even this unsustainable setup for at least a year. We just want to be more efficient with our and others resources going forwards.

That's what all this you might have heard of is about.

Btw, even if the binary cache were to go poof, we don't technically need it. NixOS is a source-based distro like Gentoo and source hosting is not a concern. The binary cache is immensely helpful though which is why we'd obviously prefer to keep it.

A simple bash script is not reproducible or deterministic. Also a filesystem rollback is not the same as NixOS's generation based rollback.

Also, NixOS doesn't just install packages, all system configuration is done declaratively, which would be a very bad idea to do via a bash script.

There is a world of difference between a bash script and something like NixOS. The most important difference is that with NixOS something that you don't specify won't be there. Whereas a bash script (or other config management tools like Puppet, Chef or Ansible) only mutate things listed.

So it is very easy to write a script like:

 undefined

    
ensure_installed python3
write_file /etc/foo.cfg 'thing = 7'
chgrp users /mnt/backups

  

But if you remove ensure_installed python3 it will stay installed. You can try to be very careful and always add ensure_not_installed python3 but this is both error prone and dead code as soon as you run it. I used to have a script like this and I used each of configuration management tools mentioned above and always ran into these issues. The exact error flow would be something like this:

1. Enable/setup some service A that pulls in package X.
2. Disable service A or remove package X because it isn't needed anymore.
3. Write configuration for service B.
4. Forget to add ensure_installed X but it works anyways because X is still installed from step 1.

Now you have a non-reproducible config because if you try to re-install or setup service B on a new machine it won't work because X isn't present. This may sound like a niche problem but I ran into it almost every time I tried to bring up a new machine using my config.

It is still possible to do this in NixOS as it isn't completely reproducible (you can have mutable state) but in general it is much harder because any configuration that isn't specified doesn't exist. As soon as you remove package X or service Y from your config it is removed from your system. I've been using NixOS for 8 years now and this problem is mostly gone. It is definitely more reproducible than bash scripts and it has a tangible effect on my workflow.

I wrote a blog post about it a long time ago but the core is still relevant: https://kevincox.ca/2015/12/21/service-management-with-nixos/.

Part of the purpose of NixOS is providing a means to build a reproducible environment that's easy to configure, migrate, and rollout. You can absolutely handle configuration of many different programs using either flakes or the native modules provided by nix. You can customize your entire system from firewall entries, to users and their shells, to the kernel itself and the kernel modules you'd want it to load, all in a single file or multiple files. If you want to try doing all those things in bash scripts, good luck and please share your experiences but don't expect it to be as easy as the Nix ecosystem.

Agreed, Silverblue is great. I would love a declarative system, but Nix just doesn't make it easy with its sprawling documentation and mix of new and old parts. I was trying to follow a guide for Home Manager, but couldn't use it because they were using flakes, I was still on the "old" configuration.nix style.

You can't make all things declarative either. If I can only have things 50% declarative, it kinda defeats the point.

I also still tried to use flatpaks since nix doesn't have sandboxing and is slower on updates, but its font configuration was broken.

Nix overall feels like it's requires a lot of workarounds, moreso than Silverblue.

But hey, at least if I ever want to try it out again, I just need to copy in my configuration.nix and make things work from there.