nix/evaluator.nix in confctl-1.0.0 vs nix/evaluator.nix in confctl-2.0.0

@@ -16,12 +16,12 @@
   };
 
   nameValuePairs = builtins.map (m: {
     name = m.name;
     value = {
-      inherit (m) name;
-    } // m.config;
+      inherit (m) name alias clusterName carrier metaConfig;
+    };
   }) machines;
 
   machinesAttrs = builtins.listToAttrs nameValuePairs;
 
   fullMachinesAttrs = builtins.listToAttrs (builtins.map (m: {
@@ -51,11 +51,11 @@
 
   machineSwpins = m:
     import ./lib/swpins/eval.nix {
       inherit (arg) confDir;
       name = m.name;
-      channels = m.config.swpins.channels;
+      channels = m.metaConfig.swpins.channels;
       pkgs = corePkgs.pkgs;
       lib = corePkgs.lib;
     };
 
   coreSwpinsAttrs = coreSwpins.evaluated;
@@ -68,20 +68,31 @@
   selectedToplevels = builtins.listToAttrs (builtins.map (host: {
     name = host;
     value = buildToplevel fullMachinesAttrs.${host};
   }) arg.machines);
 
-  buildToplevel = m: (evalMachine m).config.system.build.toplevel;
+  buildToplevel = machine:
+    let
+      machineConfig = (evalMachine machine).config;
 
-  evalMachine = m:
+      buildAttr = coreLib.attrByPath machine.build.attribute null machineConfig;
+
+      result =
+        if isNull buildAttr then
+          abort "Attribute 'config.${coreLib.concatStringsSep "." machine.build.attribute}' not found on machine ${machine.name}"
+        else
+          buildAttr;
+    in result;
+
+  evalMachine = machine:
     let
       importPath = {
         nixos = <nixpkgs/nixos/lib/eval-config.nix>;
         vpsadminos = <vpsadminos/os/default.nix>;
       };
 
-      evalConfig = import importPath.${m.config.spin} {
-        modules = [ m.build.toplevel ];
+      evalConfig = import importPath.${machine.metaConfig.spin} {
+        modules = machine.extraModules ++ [ machine.build.toplevel ];
       };
     in evalConfig;
 
   evalConfctl =
     let