hallettj

I think you can mount an ISO image under your running system and make changes. I found a couple of guides that might be helpful:

How to Mount an ISO File on Linux

Edit and repack .iso bootable image

I haven't done this before, but I think you can chroot into the mount directory, and run package manager commands in the mounted image to install another package.

Or I have an alternative suggestion that might or might not be easier. I've been hearing a lot about immutable/atomic distros, and people designing their own images. You could make your own ublue image, for example, with whatever you want on it.

A promising looking starting point is github:ublue-os/startingpoint. Ignore the "Installation" instructions, and follow the "ISO" instructions instead.

Or I saw recently an announcement of a new way to build atomic images that is supposed to be easier than ever, BlueBuild

Well you're really feeding my Nix confirmation bias here. I used to use Ansible with my dot files to configure my personal computers to make it easy to get set up on a new machine or server shell account. But it wasn't great because I would have to remember to update my Ansible config whenever I installed stuff with my OS package manager (and usually I did not remember). Then along came Nix and Home Manager which combined package management and configuration management in exactly the way I wanted. Now my config stays in sync because editing it is how I install stuff.

Nix with either Home Manager or NixOps checks all of the benefits you listed, except arguably using a "known" programming language. What are you waiting for?

Well ok, they both use symlinks but in different ways. I think what I was trying to say is that in NixOS it's symlinks all the way down.

IIUC on Fedora Atomic you have an ostree image, and some directories in the image are actually symlinks to the mutable filesystem on /var. Files that are not symlinks to /var (and that are not inside those symlinked directories), are hard links to files in the ostree object store. (Basically like checked-out files in a git repository?)

On NixOS this is what happens if examine what's in my path:

$ which curl
/run/current-system/sw/bin/curl

$ ls -l /run | grep current-system
/run/current-system -> /nix/store/p92xzjwwykjj1ak0q6lcq7pr9psjzf6w-nixos-system-yu-23.11.20231231.32f6357

$ ls -l /run/current-system/sw/bin/curl
/run/current-system/sw/bin/curl -> /nix/store/r304lglsa9i2jy5hpbdz48z3j3x2n4a6-curl-8.4.0-bin/bin/curl

If I select a previous configuration when I boot I would get a different symlink target for /run/current-system. And what makes updates atomic is the last step is to switch the /run/current-system symlink which switches over all installed packages at once.

I can temporarily load up the version of curl from NixOS Unstable in a shell and see a different result,

$ nix shell nixpkgs-unstable#curl  # this works because I added nixpkgs-unstable to my flake registry
$ which curl
/nix/store/0mjq6w6cx1k9907vxm0k5pk7pm1ifib3-curl-8.4.0-bin/bin/curl  # note the hash is different

I could have a different version curl installed in my user profile than the one installed system-wide. In that case I'd see this:

$ which curl
/home/jesse/.nix-profile/bin/curl

$ ls -la /home/jesse | grep .nix-profile
.nix-profile -> /nix/var/nix/profiles/per-user/jesse/profile

$ ls -l /nix/var/nix/profiles/per-user/jesse
profile -> profile-133-link
profile-130-link -> /nix/store/ylysfs90018zc9k0p0dg7x6wvzqcq68j-user-environment
profile-131-link -> /nix/store/9hjiznbaii7a8aa36i8zah4c0xcd8w6d-user-environment
profile-132-link -> /nix/store/h4kkw1m5q6zdhr6mlwr26n638vdbbm2c-user-environment
profile-133-link -> /nix/store/jgxhrhqiagvhd6g42d17h4jhfpgxsk3n-user-environment

Basically symlinks upon symlinks everywhere you look. (And environment variables.)

So I guess at the end everything is symlinks on NixOS, and everything is hard links plus a set of mount paths on Fedora Atomic.

If you put an FHS on the actual system you wouldn't be able to install multiple versions of the same package, updates wouldn't be atomic - you wouldn't get the big selling points of Nix.

"Atomic" is a catchy descriptor! Atomic distros for the Atomic Age! It could be an umbrella term since NixOS and Guix are atomic, but instead of images and partitions they use symlinks, and patch binaries to use full paths for libraries and programs that they reference. So there are image-based distros, and I guess expression-derived distros which are both atomic.

I haven't tried image-based distros. This post fills in some gaps for me. Thanks for the write-up!

Although they're not in the search, they are in the manual so you can find them searching that page. This one is listed as,

security.pam.services..fprintAuth

But it does take some inferences to find this, and to realize that you can put doas in place of ``

I did some digging around in the manual, and I tested this option which seems to work:

security.pam.services.doas.fprintAuth = true;

On my machine that adds this line to /etc/pam.d/doas:

auth sufficient /nix/store/fq4vbhdk8dqywxirg3wb99zidfss7sbi-fprintd-1.94.2/lib/security/pam_fprintd.so # fprintd (order 11400)

Edit: Note that the NixOS option puts in the full path to pam_fprintd.so. That's necessary because NixOS doesn't put so files in search paths.

Without doing more research I don't know how to add arbitrary options to pam files in case you run into something that isn't mapped to a NixOS option yet. The implementation for the pam options is here; there might be something in there that would work.

Wayland replaces the older X protocol. It doesn't have to operate with older protocols. You might be thinking of XWayland which is a proxy that receives X API calls from apps written for X, and translates those to the Wayland API so that those apps can run under Wayland implementations. Window managers can optionally run XWayland, and many do. But as more apps are updated to work natively with Wayland, XWayland becomes less important, and might fade away someday.

PipeWire replaces PulseAudio (the most popular sound server before PipeWire). Systems running PipeWire often run pipewire-pulse which does basically the same thing that XWayland does - it translates from the PulseAudio API to the PipeWire API. It's a technically optional, but realistically necessary compatibility layer that may become less relevant over time if apps tend to update to work with PipeWire natively.

So no, both Wayland and PipeWire are capable of operating independently of other protocols.

NixOS puts your full system configuration in a portable set of files. You can easily reproduce the same configuration on another machine. I also like that instead of accumulating a growing list of packages that I don't remember why I installed I have package lists specified in files with comments, and split into modules that I can enable or disable.

IMO NixOS works best when you also use Home Manager to apply the same benefits to your user app configurations and such. (OTOH you can use Home Manager to get those benefits without NixOS. But I like that I get consistency between the OS-level and user-level configurations, and that both use the same set of packages.) I use Home Manager to manage my list of installed packages, my dot files, Gnome settings, Firefox about:config settings, and so on.

You might be installing packages imperatively with nix profile install or with nix env -i. If that's the case you're not going to see the full benefits of a declarative system in my opinion. I prefer to install packages by editing my Home Manager configuration and running home-manager switch.

I like that NixOS + Home Manager automates stuff that I used to do by hand. A couple of the things that I do or have done are to,

• test an experimental window manager, Niri
• use Neovide (a GUI frontend for Neovim) with a custom patch to tweak font rendering

Now I have that kind of stuff automated:

• Since there was no packaging for Niri when I started trying it I wrote my own in my NixOS config with a NixOS module to set up a systemd unit to run it. Because Nix packages are effectively build scripts, whenever I update Nix automatically pulls the latest version of Niri and compiles it without me having to think about it anymore.
• I use the Neovide package from nixpkgs with an override to compile with my custom patch. Like with Niri my configuration automatically gets the latest Neovide version and builds it with my patch when I update, and I don't have to think about it anymore. I use this overlay to do that:

modifications = final: prev: {
  neovide = final.neovide.overrideAttrs (oldAttrs: {
    patches = (oldAttrs.patches or [ ]) ++ [ ./neovide-font-customization.patch ];
  });
};

You can see that I compile some things from source. That's fine on my desktop, but takes a while on my travel laptop. But I don't need to compile on my laptop because I can use Nix's binary cache feature. I push my NixOS and Home Manager configurations to Github, and I have Garnix build everything that I push. Garnix stores everything it builds in a binary cache. So when I pull my latest configuration version on my laptop it downloads binaries from that cache.

Sharing the link because it took me a minute to find it: https://codeberg.org/dnkl/fuzzel

I'm also a PaperWM fan. For switching I mostly use spatial window-switching controls: Meta+ left/right to switch windows, page up/page down to switch workspaces. Plus I use Gnome overview's search-driven app finder, and Advanced Alt-Tab Switcher but only for its fuzzy search feature to switch to specific windows within an app.

PaperWM has an option to hide windows in a "scratch" layer. I put chat and music programs there, and summon them with AATS.

I have an ultrawide monitor, and I put a terminal and editor side-by-side in a ¼-¾ ratio. I set browser windows to ½ width. Those ratios let me see important parts of a browser window next to the editor if I slide the terminal out of view to partially expose a browser on the other side. Or I can move the terminal next to the browser and see both fully.

I sometimes write a flake with those 4 lines of Nix code, and it comes out just messy enough that tbh I'm happier adding an input to handle that. But I recently learned that the nixpkgs flake exports the lib.* helpers through nixpkgs.lib (as opposed to nixpkgs.legacyPackages.${system}.lib) so you can call helpers before specifying a system. And nixpkgs.lib.genAttrs is kinda close enough to flake-utils.lib.eachSystem that it might make a better solution.

Like where with flake-utils you would write,

flake-utils.lib.eachSystem [ "x86_64-linux" "aarch64-darwin" ] (system:
let
  pkgs = nixpkgs.legacyPackages.${system};
in
{
  devShells.default = pkgs.mkShell {
    nativeBuildInputs = with pkgs; [
      hello
    ];
  };
})

Instead you can use genAttrs,

let
  forAllSystems = nixpkgs.lib.genAttrs [ "x86_64-linux" "aarch64-darwin" ];
  pkgs = forAllSystems (system:
    nixpkgs.legacyPackages.${system}
  );
in
{
  devShells = forAllSystems (system: {
    default = pkgs.${system}.mkShell {
      nativeBuildInputs = with pkgs.${system}; [
        hello
      ];
    };
  });
}

It's more verbose, but it makes the structure of outputs more transparent.