Clean up vm config file

lib/config/custom-build-vm.nix

@@ -16,37 +16,6 @@ let
         (item: { inherit (item) file value; }));
 
   vanillaVM = mergedSystemOption.mergedValue.vm;
-
-  createVMWrapper =
-    vm:
-      if (vm.name == packageName)
-      then
-        vm
-      else
-        let
-          prefix =
-            lib.concatStringsSep " " (
-              lib.optionals config.virtualisation.runAsRoot (
-                ["sudo"] ++
-                lib.optional config.virtualisation.qemu.runInBackground "-b"));
-
-          suffix =
-            lib.concatStringsSep " " (
-              lib.optional
-                (!config.virtualisation.runAsRoot && config.virtualisation.qemu.runInBackground)
-                "&");
-
-          wrapped = pkgs.writeShellApplication {
-            name = "run-${config.system.name}-vm";
-            text = ''
-              ${prefix} ${vm}/bin/run-${config.system.name}-vm ${suffix}
-            '';
-          };
-        in
-          pkgs.symlinkJoin {
-            name = packageName;
-            paths = [ wrapped ];
-          };
 in {
   options =
   let
@@ -106,7 +75,38 @@ in {
     # Replace native `qemu` with `remote-viewer`
     system.build =
       {
-        vm = lib.mkForce (createVMWrapper vanillaVM);
+        vm = lib.mkForce (
+          (
+            vm:
+              if (vm.name == packageName)
+              then
+                vm
+              else
+                let
+                  prefix =
+                    lib.concatStringsSep " " (
+                      lib.optionals config.virtualisation.runAsRoot (
+                        ["sudo"] ++
+                        lib.optional config.virtualisation.qemu.runInBackground "-b"));
+
+                  suffix =
+                    lib.concatStringsSep " " (
+                      lib.optional
+                        (!config.virtualisation.runAsRoot && config.virtualisation.qemu.runInBackground)
+                        "&");
+
+                  wrapped = pkgs.writeShellApplication {
+                    name = "run-${config.system.name}-vm";
+                    text = ''
+                      ${prefix} ${vm}/bin/run-${config.system.name}-vm ${suffix}
+                    '';
+                  };
+                in
+                  pkgs.symlinkJoin {
+                    name = packageName;
+                    paths = [ wrapped ];
+                  })
+          vanillaVM);
       };
   };
 }