NixOS: A Personal Post-Mortem

> because the nix view is that it's absurd having 7 different package managers fighting for control of the same system

And addresses that by becoming the 8th different package manager fighting for control of the same system, a la https://xkcd.com/927/

Except the entire argument here is that it doesn't cooperate very nicely with other package managers so I'm not sure how your point holds together.

> No, I think it's a very sensible assumption.

The problem is it's an "assumption" that is rarely easy to correct when it's wrong.

> As far as I can see, virtually every GNU/Linux OS has shared libraries in /use/lib, and it even has crude support for versioning.

If that were a satisfactory assumption there would be no need for sledgehammer solutions like docker.

> it even has crude support for versioning.

which is extremely unstandardised and frequently goes very wrong and will end up compiling against a mismatched set of headers and libraries.

> Nix's approach is a break from the norm, so really it has the responsibility of maintaining compatibility.

It doesn't really have any responsibility for anything apart from doing what its users want from it. And by and large it does that.

> the existing standard Python tools everyone uses

The "existing standard python tools" (pip, virtualenv, pyenv, tox...) are ~5 different attempts at solving the same problem, but each time failing to do so, giving rise to yet another tool. Properly applied, Nix can address all of them.

It really doesn't sound like you want Nix at all - you appear to be arguing for the de-facto standard approach from the last 2-3 decades, which is not what Nix is. It is a deliberate departure from that. These design decisions that appear to annoy you aren't arbitrary choices that Nix people made to be difficult, they are core to how Nix works.

If you want something that will present a facade that it's a linux system from the last 2 decades while still appearing to give you some of the advantages of isolated/pseudo-reproducible environments, what you want is docker.

I’ve been using nixos for a solid 2 years. I was introduced to nix 5 years ago when a developer at a company I worked for introduced it for one of the developer environments. In those 3 intervening years, I went from thinking that nix was incredibly stupid to thinking that nix had some good ideas and I should try it. All of that is to say, that I have some knowledge of nix. I think most of the criticisms are fair.

Developer environments are my favorite usage of nix. To me, they deliver on the promise but, there’s a big caveat, dealing with languages that need native libraries is a real pain. The mentioned buildFHSUserEnv is basically a last resort. There are better solutions but they require a great deal more fiddling. I find that my start up time for getting a developer environment going is very long, sometimes 10x longer than just installing it in Ubuntu on a fresh vm. I find it is worthwhile to go through this process as I then don’t have to worry about being able to recreate it or switch between very incompatible projects. Luckily for me, the ecosystem that I frequently have to deal with this with is python and poetry2nix works pretty well (with some rough edges). mach-nix made this even easier but it is abandoned in favor of dream2nix which isn’t ready.

The learning curve for nix is intense. It is incredibly unfamiliar and useful information is widely spread (the main documentation was too dense for me to comprehend when I started). Read the post, it seems to me that the author never got over the learning hump into it actually being useful. I think that is a perfectly rational choice, it isn’t the right thing for everyone. The one thing that kept me going through the first year of the learning process was one of the things that the author didn’t find important, being able to boot to a previous configuration. I don’t have to worry about updates that break something or making a bad configuration change. If I update my system and something breaks, at worst, I can simply reboot to revert to the previous configuration until I’m ready to troubleshoot the issue.

Nix also does itself a disservice but not promoting flakes as the nix way. Using channels makes reproducibility much worse.

Interesting take.

For me it was quite the opposite, regular Linux distributions annoyed me because after having them set up, some stupid mistake (either from my side, or from upstream, unsure about this) caused my whole bootloader to break, rendering my system unrecoverable (maybe not for every, but for me it was/is).

When i learned about NixOS, allowing you to essentially set up your whole system declaratively, it was so compelling to me, that i just went with it. Yea i don't really like / know the language very well, but it's a lot better of an experience than any prior Linux experience i made.