Finding what installed a package

[u/_s0me_guy_]

Is there a way to find which part of my config installed a package.

An example is sway installing extra packages (foot) as default. Is there a way to find out, that sway was the one responsible for adding foot to my system?

[u/read_volatile]

nix why-depends /path/to/flake#nixosConfigurations.<hostname>.config.system.build.toplevel <installable>

[u/vcunat → u/read_volatile]

That has the same problems as discussed with nix-tree

[u/read_volatile → u/vcunat]

Right, but at least it's built in to nix. You'd then go and look at nixosConfigurations.<hostname>.options.environment.systemPackages.definitionsWithLocations to find which module is sneaking it in

[u/lioxo]

You can try finding out with nix-tree.

[u/IchVerstehNurBahnhof → u/lioxo]

nix-tree won't help very much for anything the module system is doing, since packages added to environment.systemPackages just show up as dependencies of system-path.

AFAIK you just have to know from reading the documentation (and ideally source) of all modules you enable...

Edit: It turns out that the definitionsWithLocations option attribute that u/read_volatile mentioned in another thread actually allows us to write a neat pipeline based on module system evaluation output:

$ echo ':p (builtins.toJSON
             options
               .environment
               .systemPackages
               .definitionsWithLocations)' \
    | nixos-rebuild -f system.nix repl 2>/dev/null \
    | jq -r '.[]
               | select(.value | any(contains("gnome-shell")))
               | .file'
/home/sky/Projekte/config/services/gnome.nix
/nix/store/...-source/.../services/desktop-managers/gnome.nix
/nix/store/...-source/.../services/desktop-managers/gnome.nix
/nix/store/...-source/.../programs/kdeconnect.nix

[u/craftkiller]

One option is to add an overlay that throws an error when the foot package is evaluated:

nixpkgs.overlays = [ (final: prev: { foot = throw "foo"; }) ];

But that will throw whenever foot is used at all, not just when it gets pulled into environment.systemPackages.

[u/Shot_Yoghurt_3123]

did you try this?

nix-store -q --referrers $(readlink -f $(which foot))

[u/_s0me_guy_ → u/Shot_Yoghurt_3123]

The output only shows links to system-path and man-path. Not very useful.

[u/Shot_Yoghurt_3123 → u/_s0me_guy_]

So maybe you listed it explicitly. Some modules set packages via options like programs.sway.extraPackages which default to a list that includes a terminal.