I was thinking only about user services for programs I installed. Not intending to mess with system services or otherwise critical stuff.

Thanks.

ElvishJerricco:

       … while calling the 'derivationStrict' builtin
         at <nix/derivation-internal.nix>:34:12:
           33|
           34|   strict = derivationStrict drvAttrs;
             |            ^
           35|

       … while evaluating derivation 'image'
         whose name attribute is located at /nix/store/l9nb64iii15y0nr37qrs1cfm6rlpg6gh-source/pkgs/stdenv/generic/make-derivation.nix:375:7

       … while evaluating attribute 'definitionsDirectory' of derivation 'image'
         at /nix/store/l9nb64iii15y0nr37qrs1cfm6rlpg6gh-source/nixos/modules/image/repart-image.nix:118:27:
          117|
          118|   inherit finalPartitions definitionsDirectory;
             |                           ^
          119|

       … while evaluating the option `image.repart.partitions.root.storePaths':

       … while evaluating definitions from `/nix/store/dhrgxhkn9hy0w1wqsaq9zsm5qyyrg5ji-source/machine-specific/katla-asahi-generic/repart.nix':

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/l9nb64iii15y0nr37qrs1cfm6rlpg6gh-source/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `image.repart.partitions.store.repartConfig':

       … while evaluating definitions from `/nix/store/dhrgxhkn9hy0w1wqsaq9zsm5qyyrg5ji-source/machine-specific/katla-asahi-generic/repart.nix':

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

       error: infinite recursion encountered
       at /nix/store/l9nb64iii15y0nr37qrs1cfm6rlpg6gh-source/lib/modules.nix:846:9:
          845|     in warnDeprecation opt //
          846|       { value = addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          847|         inherit (res.defsFinal') highestPrio;

...
    image.repart = {
      name = "image";
      partitions = {
        "store" = {
          storePaths = [ config.system.build.toplevel ];
          stripNixStorePrefix = true;
          repartConfig = {
            Type = "linux-generic";
            Label = "nix-store";
            Format = "erofs";
            Minimize = "guess";
          };
        };
        "esp" = {
          contents = {
            "/EFI/BOOT/BOOT${lib.toUpper efiArch}.EFI".source =
              "${pkgs.systemd}/lib/systemd/boot/efi/systemd-boot${efiArch}.efi";

            "/EFI/Linux/${config.system.boot.loader.ukiFile}".source =
              "${config.system.build.uki}/${config.system.boot.loader.ukiFile}";
          };
          repartConfig = {
            Type = "esp";
            Format = "vfat";
            SizeMinBytes = "96M";
          };
        };
      };
    };
...