modified config for more modularity

modules/host-users.nix

@@ -1,5 +1,7 @@
 {
-  username,
+  lib,
+  pkgs,
+  userName,
   hostname,
   ...
 } @ args:
@@ -14,10 +16,13 @@
   system.defaults.smb.NetBIOSName = hostname;
 
   # Define a user account. Don't forget to set a password with ‘passwd’.
-  users.users."${username}" = {
-    home = "/Users/${username}";
-    description = username;
+  users.users."${userName}" = {
+    home =
+      if pkgs.stdenv.isDarwin
+      then "/Users/${userName}"
+      else "/home/${userName}";
+    description = userName;
   };
 
-  nix.settings.trusted-users = [username];
+  nix.settings.trusted-users = [userName];
 }