[microvm] fix comparision

this reduces build times drastically

machines/configuration.nix

@@ -46,6 +46,11 @@ let
     {
       microvm = {
         hypervisor = "qemu";
+        shares = [ {
+          tag = "ro-store";
+          source = "/nix/store";
+          mountPoint = "/nix/.ro-store";
+        } ];
         interfaces = [
           {
             type = "tap";

machines/modules/malobeo/microvm_host.nix

@@ -13,6 +13,14 @@ in
         type = types.bool;
         description = lib.mdDoc "Setup bridge device for microvms.";
       };
+
+      deployHosts = mkOption {
+        default = [];
+        type = types.listOf string;
+        description = ''
+          List hostnames of MicroVMs that should be automatically initializes and autostart
+        '';
+      };
     };
   };
 
@@ -48,5 +56,24 @@ in
         networkConfig.Bridge = "microvm";
       };
     };
+
+    imports = mkIf (lib.length cfg.deployHosts != 0) [
+      inputs.microvm.nixosModules.host
+    ];
+
+    microvm.autostart = cfg.deployHosts;
+    microvm.vms = 
+    let
+      # Map the values to each hostname to then generate a Attrs using listToAttrs
+      mapperFunc = name: { inherit name; value = {
+          # Host build-time reference to where the MicroVM NixOS is defined
+          # under nixosConfigurations
+          flake = self;
+          # Specify from where to let `microvm -u` update later on
+          updateFlake = "git+https://git.dynamicdiscord.de/kalipso/infrastructure?ref=microvm";
+        }; };
+    in
+    mkIf (lib.length cfg.deployHosts != 0)
+    builtins.listToAttrs (map mapperFunc cfg.deployHosts);
   };
 }