Basically, I want to be able to run completely unverified code off of the internet on my local machine, and know that the worst thing it can possibly due is trash its own container.

I feel like NixOS, is one path toward getting to that future.

It will always look like curl is available or bash or something

What's wrong with another user account for such isolation?

They can be isolated to namespaces and cgroups. Docker and Nix are just wrappers around a lot of OS functionality with their own semantics attempting to describe how their abstraction works.

Every OS already ships with tools for control users access to memory, disk, cpu and network.

Nix is just another chef, ansible, cfengine, apt, pacman

Building ones own distro isn't hard anymore. If you want ultimate control have a bot read and build the LFS documentation to your needs.

Nothing more powerful than the raw git log and source. Nix and everything else are layers of indirection we don't need

If it isn't enough there's microvm.nix which is pretty much the same in difficulty /complexity, but runs inside a very slim and lightweight VM with stronger isolation than a container

I am no nix whiz, but it's the only OS I run outside of containers. Anything I can't easily get with my nix config I shove into a container, run it as a quadlet, and call it good.

Also, using higher level modules like home manager makes things more declarative and less fiddly since someone else is maintaining the lower level.

Maybe nix is a downgrade for what you do. But I loved nix so much that I also migrated to nix on macOS (nix-darwin). No more homebrew.

The advantages:

- Declarative code describes your system. Maybe your install + imaging flow is good enough, but there are many reasons why it's technically inferior. There's no need for imaging Nix, because it's always reproducible by default. Rollbacks are rebooting to a previous config, not a timestamped blob of snowflake state.

- It replaces whatever tools and glue you have to build your system. You don't need to worry about bootstrapping tools, or config management tools' version compatibility, or bespoke ordering of imperative steps to build the system. All the management tools are built into the system. Everything "just works" automatically.

- If you manage multiple machines the benefits are compounding.

- There are other interesting bits that are covered in the article, that you get for free just due to the nature of nix. It's good for building, and has no friction to experimenting with specific tools or environments, without polluting your system.

It's a commitment to get past the initial learning and config build, but afterwards it significantly lessens the "hobby" aspects of computer management. There are just entire classes of problems that don't exist for Nix. Either your config works, or it doesn't, and the rollback guarantee is explicit and built-in.

[0]: https://nixos-and-flakes.thiscute.world

I haven't tried it in almost a year, but using Claude Code for setting up my nix config back then worked amazingly well. I've only dabbled in NixOS, and I'm very tempted to it for my workstation when I reinstall it in the next month.

Given how much Claude Code + Opus have improved in the last year, I'd give it a fighting chance to make a nice Nix config. I'll probably start setting up a spare laptop to get the base configs dialed in before switching over to it.

Using AI to generate Nix config is a superpower. Because the entire system is declared in a single set of config, you can basically spell cast any system you want. I one-shotted a Linux distro with custom branding for boot, installation screen, and login screen, and VPN and dev tools installed and configured by default, at a fortune 500 tech company.

    { pkgs }:
    
    pkgs.mkShell {
      nativeBuildInputs = with pkgs; [
        # build tools
        cmake
        ninja
        gnumake
        pkg-config
      ];
    
      buildInputs = with pkgs; [
        # java
        jdk8
    
        # compilers
        gcc
        clang
        llvmPackages.libcxx
    
        # libraries
        capstone
        icu
        openssl_3
        libusb1
        libftdi
        zlib
    
        # scripting
        (python3.withPackages (ps: with ps; [
          requests
          pyelftools
        ]))
      ];
    
      # capstone headers are in include/capstone/ but blutter expects include/
      shellHook = ''
        export CPATH="${pkgs.capstone}/include/capstone:$CPATH"
        export CPLUS_INCLUDE_PATH="${pkgs.capstone}/include/capstone:$CPLUS_INCLUDE_PATH"
      '';
    }

As best I can tell, Nix enthusiasts think that this is an XY problem and that I shouldn't want to pin individual tools/packages to arbitrary versions. But the thing is that I am a rude barbarian who very much does want to do this, however philosophically misguided it might be.

wiki.nixos.org claims that nixos.wiki is outdated and unofficial. But both appear to receive updates, and which one wins the SEO game is a coinflip whenever i google a nixos question.

The downside is that flake inputs refer to other flakes, not individual packages, so if you update the nixpkgs input it will upgrade all of your packages at once. For some packages such as Python, nixpkgs tracks multiple major versions so you can loosely pin to that version. You can also include nixpkgs as an input multiple times under different git tags/commits and only use that input for some of your packages to effectively pin them. You could keep using one nixpkgs but override the package's source to build it for a specific version/commit, but this setup could break in the future, because the derivation (and therefore build instructions) will keep evolving while your package's version will not. Or, if you really wanted to, you could straight up just copy the derivation from nixpkgs into your local repository and use that instead.

Nix is quite flexible so there's more options than just these, it just takes a little getting used to to find out what's possible. I don't use devenv myself, but some quick googling reveals it works just fine with flakes, so I would try that to see if it suits your needs.

Claude Code has to be actively steered, because while it knows some nixpkgs it surely doesn’t know it enough. E.g. it was absolutely incapable of fixing lldap settings after system upgrade from 25.05 to 25.11. It just prodded around blindly, producing meaningless configs instead learning how the module works.

NixOS docs work for me, but I tend to just go for the nixpkgs source instead. Manuals document options but not how those are actually plumbed through, nor what remains behind the scenes like all systemd unit settings). Claude can do this too, but it goes quite weird roundabout ways with a lot of weird `find /nix/store` and `nix eval`s to get to it, slow and token-hungry (and not always accurate).

This said, Claude is very helpful at checking logs and providing a picture of what’s going on - saves ton of time this way. Plus it can speed up iterating on changes after it’s fed enough knowledge (but don’t expect it to do things right, that’s still on you). It has breadth of it, but not the depth, and that shows at almost any non-trivial task.

Like what is ultimately the difference here for you vs a non-nix user who, as author says, is just dealing with some big ambiguous pile of state? It kind of takes away any upside to using nix, and probably just creates more friction for your AI than just running ubuntu/apt stuff.

The idea is you can keep configuration "in your head" such that you can reason and iterate and fully know what your system is like at any moment. If you actually don't care about that, you aren't getting anything out of it!

That is in between "use it for very short period of time" and "use it forever"

If you don't mind a very limited set of software, the way tinycorelinux is setup can also allow multiple different tcz installed

These two Linux distros essentially allow two different versions of same software/libraries (glibc/python whatever) installed

(Gobolinux explicitly states that whereas I find it to be an unintended but elegant consequence for tinycorelinux but I recommend taking a look at Gobolinux)

I am not a fan of S-expressions but using scheme is more reasonable than nix+bash to me.

On the negative side, guix can be slow. It is also not a very pragmatic os. NixOS does non-free firmware and drivers without issue. You need to jump through some hoops for this with Guix. This is not an issue if you plan to run guix in a VM though.

I tried Discord, and this one seems to download some updates on first run, but the version sticks to the one from the system (0.0.127, latest is 0.0.129). So I assume it just doesn't update, or it tries to and fails.

right now I have bought into the Nix koolaid a bit.

I have NixOS Linux machines and then nix-darwin on my Mac.

I use Nix to install Brew and then Brew to manage casks for things like Chrome what I'm sure updates itself. So the "flake.lock" probably isn't super accurate for the apps you described.

For some things I've vibe-coded a nix module on github that uses a scheduled github action to check for underlying app updates and then it generates a new hash and tags a release.

I've done that for claude code and cursor, which is also an opportunity to let me manage their config files from my nix config.

I also tried fedora coreos for a vm + container host, but found the recommended method to configure the system with ignition files and one shot systemd units to be too involved for making a one off system, and it’s probably better for a cloud deployment with many identical nodes.

Jetbrains Toolbox is in a sort of different category with tools like Rustup, since it's a package manager of its own. If you manage your IDEs with Toolbox, then your IDE versions are "outside Nix" and not managed by Nix. It's just packaged into its own pretend FHS environment and then doesn't know anything about it being on Nix. That said, updates of Toolbox itself will need to happen through your package manager.

As a last comment, why run Docker Desktop on Linux at all? Like I understand on Windows and Mac - docker is inherently tied to Linux so the Windows/Mac apps abstract away the fact that it's running a VM and doing a bunch of port mapping and filesystem mounting under the hood so you can pretend it's not running on a VM, but on Linux I've always just installed docker straight onto the host.

If you’re itching to try Nix, now is the time.

> How do I set up my development environment using devenv.sh to pin nodejs to 24.14.0?

If I understand your response correctly, I can't do this in any very practical way.

I feel you on the nix store + nix eval death loop, though it gleans real info. If I weren't on the Claude Max plan I'd probably feel more of the pain. And context is now 1MM tokens which means you're not running out just as it's starting to piece things together, heh.

I have these packages installed and these firewall settings and these users with these permissions and this folder served over Samba and these hotkeys that do these things and these Obsidian vaults synced over SyncThing and these devices in my SyncThing network and Neovim installed with these plugins and ...

This is difference between me and a non-nix user, not whether we can rattle off the exact state of our live system from memory.

The non-nix user has to query live system state, if such query tools even exist for their question, and I get to read a config file. And I get to maintain my system config in git, and I get to deploy my config on all of my machines.

The true answer is that there is just some software that is antithetical to the philosophy of nix. It’s not necessarily nix’s fault that this is the case, but their purism towards resisting opaque binary blobs going into the store reflects on the actual state of what’s available in nix.

You need some impure, nonreproducible way of managing that software. So on nix Darwin I let these opaque binary blobs manage themselves via homebrew and use nix for every other case possible

Unless you're brand new to Linux or computing, it's not a mystery what a given nix config change is ever doing.

You can probably guess what this does:

    networking.firewall.allowedTCPPorts = [ 8080, 9000 ];

Nixpkgs is very complete in my experience, and in the instances where its not, someone usually has made a flake. The only times ive had to custom-make a flake were extremely new programs, or extremely old ones. Often the newer programs had PRs waiting on nixpkgs anyway, and were only a few days away from building properly in nixos-unstable.

1. Unified experience across Windows, Mac, Linux

2. The security posture is much stronger by default. Many people, who would probably be considered the “target audience” for Docker Desktop, don’t bother to make docker-ce rootless, or don’t use podman, so running it in a VM is better, though admittedly often annoying.

3. Not everybody is a CLI warrior. Docker Desktop gives a decent GUI, ways to monitor and control containers visually, and even deploy kubernetes with a single click.

Regarding Docker Desktop on Linux - yeah definitely not strictly necessary. Sometimes it’s just convenient to have a UI instead of fumbling around trying to remember some cli incantation to check for dangling volumes or what-have-you. I think ideally I want to move to Podman anyways - but I’m using pop_os as my dev distro at the moment and am stuck on an older version which doesn’t have their native `podman compose` implementation yet

Can't imagine going back to the status quo where my system is the accumulation of terminal commands over time instead of a config file.

I’m going to experiment with skills next, or maybe make it build a few helper scripts for itself to quickly get some module source from nixpkgs matching flake.lock without having to think of it all. I’m positive about Claude for nix management, merely saying it’s not something that “just works” for now and reading nix code is still on the human part of the tandem.

This said, to be fair - when it gets the approach right, it excels. I was setting up Ente for photos backup and sharing, and it produced a nice overlay with custom patches for my needs from just “figure out why /shared-albums/ redirects wrong and fix”. Found the module, the package, pulled source, analyzed it, proposed a patch (settings weren’t enough), did it - I only had to test, and only because I haven’t provided it with a browser. Felt amazing.

I am not brand new - and I don't know what the heck the config is doing.

That is why I rely on documentation.

The "code is self-explanatory" is always an attempt to not have useful documentation and try to rationalise that problem away.

And there's also nix alien and similar tools as alternative

But indeed usually you end up using patchelf , tell the inputs of a binary n just make a regular nix package from it

You're right. When I tried using NixOS as my main desktop experience for a few months, I ended up with a custom derivation for various apps I used. That's probably why I made the claude code and cursor modules in the first place.

But I'm also remembering I made my own keepassxc module because keepassxc wants to be able to write to its config file, but I also want to configure it from nix, so I had to make my module use an activation-time script to merge nix config into the keepassxc config file.

I lost interest in NixOS for day to day personal computing, though vibe-coding modules like that wasn't as big of a dealbreaker as there being almost zero laptops that compete with a Macbook.

The other pain is Linux desktop environment stuff in general like dealing with interactions between a Steam game, wayland, and wayland-satellite. Though NixOS helped there since it was easy for an AI agent to investigate the issue, inspect the nix config, and make a targeted, commented patch that shows up in git.

I counted and you regularly see this: "))))))))))" at the end. This is not a language that is optimizing for being written by humans.

You can read documentation on an as-needed basis or to your heart's content.

The point is that the majority of the day to day changes I make to my desktop environment aren't so critical that I need to do more than read an AI agent's proposed changes to my config and accept them when they look reasonable.

And I don't think looking up the exact config options to NixOS' networking system does anything to increase my knowledge of the OS. It's just a triviality.

As for the closing braces, would it be better if you had a newline between each?