I'm have been getting this error on nixos-rebuild switch --upgrade for the past couple of days.
Anyone else run into this?

building Nix...
building the system configuration...
error:
       … while calling the 'head' builtin

         at /nix/var/nix/profiles/per-user/root/channels/nixos/lib/attrsets.nix:784:11:

          783|         || pred here (elemAt values 1) (head values) then
          784|           head values
             |           ^
          785|         else

       … while evaluating the attribute 'value'

         at /nix/var/nix/profiles/per-user/root/channels/nixos/lib/modules.nix:759:9:

          758|     in warnDeprecation opt //
          759|       { value = builtins.addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          760|         inherit (res.defsFinal') highestPrio;

       (stack trace truncated; use '--show-trace' to show the full trace)

       error: attribute 'evil-collection' missing

       at /nix/store/h5931chm1sy42kk73l3hkpcjwa1c0r3h-source/default.nix:99:7:

           98|     else
           99|       flake.inputs.${p};
             |       ^
          100|   # Packages we need to get the default doom configuration run

In reply to@j4:matrix.org
rabil95219: If you're interested (like I do) in getting a similar config on two different computers w/ Nix, this is what I do. (There may be other way of doing it but well, mine works well for now).
I fix the doomemacs version via home.file.".emacs.d".source = pkgs.fetchFromGitHub.... This also needs variables (session wide for instance via systemd.user.sessionVariables DOOMLOCALDIR = "$HOME/.local/share/doomemacs"; and DOOMPROFILELOADFILE = "$HOME/.local/share/doomemacs/profiles/load.el"; You need to change this because by default doom & some emacs packages expect to be able to write in .emacs.d.
Afterwards, my repo setup symlinks my emacs config between my git repo and .doom.d to get the same config. :)

How do you deal with extra config stuff then? Write out a file and load it in config.el ?
I'm asking because i used to have a setup like this with NDE

extraConfig = ''
    (setq exec-path (append exec-path '( ${
    pkgs.lib.concatMapStringsSep " " (x: ''"${x}/bin"'') extraBins
    } )))
    (setenv "PATH" (concat (getenv "PATH") ":${
    pkgs.lib.concatMapStringsSep ":" (x: "${x}/bin") extraBins
    }"))
';