parameterised username in users

hosts/common/users/media/default.nix

@@ -1,15 +1,15 @@
 { pkgs, inputs, config, lib, ... }:
 let
+  username = "media";
   pubKeys = lib.filesystem.listFilesRecursive (../keys);
   hostname = config.networking.hostName;
-  sopsHashedPasswordFile = lib.optionalString (lib.hasAttr "sops-nix" inputs) config.sops.secrets."passwords/${user}".path;
+  sopsHashedPasswordFile = lib.optionalString (lib.hasAttr "sops-nix" inputs) config.sops.secrets."passwords/${username}".path;
   secretsDirectory = builtins.toString inputs.nix-secrets;
   secretsFile = "${secretsDirectory}/secrets.yaml";
-  username = "media";
 
 in 
 {
-  users.users.${username} = {
+  users.users."${username}" = {
     isNormalUser = true;
     shell = pkgs.zsh; # default shell
     hashedPasswordFile = sopsHashedPasswordFile;
@@ -20,11 +20,15 @@ in
          "wheel" "video" "audio" "disk" "networkmanager" 
        ]; 
 
+    packages = with pkgs; [
+      flatpak
+      gnome.gnome-software
+    ];
   };
 
   environment.persistence."/persist" = {
     hideMounts = true;
-    users.${user}= {
+    users."${username}"= {
         directories = [
           "sync"
           "keep"
@@ -48,22 +52,16 @@ in
   sops.secrets."ssh_keys/${username}/id_ed25519" = {
     path = "/home/${username}/.ssh/id_ed25519";
     mode = "0600";
-    owner = config.users.users.${username}.name;
+    owner = "${username}";
   };
 
   sops.secrets."ssh_keys/${username}/id_ed25519.pub" = {
     path = "/home/${username}/.ssh/id_ed25519.pub";
     mode = "0644";
-    owner = config.users.users.${username}.name;
+    owner = "${username}";
   };
 
   services.flatpak.enable = true;
-  users.users.${username} = {
-    packages = with pkgs; [
-      flatpak
-      gnome.gnome-software
-    ];
-  };
 
   programs.zsh.enable = true;
   programs.fuse.userAllowOther = true;
@@ -71,7 +69,7 @@ in
   home-manager = {
     extraSpecialArgs = { inherit inputs; };
     users = {
-      ${username} = import ../../../../home/${hostname}.nix;
+      "${username}" = import ../../../../home/${hostname}.nix;
     };
   };
 }

hosts/sparky/default.nix

@@ -7,7 +7,7 @@ in
     [ 
       # Disk configuration
       inputs.disko.nixosModules.disko
-      (import ../common/disks/std-disk-config.nix { device = ${dev}; })
+      (import ../common/disks/std-disk-config.nix { device = dev; })
       ../common/optional/btrfs-impermanence.nix
 
       # Create users for this host