diff --git a/deployment/data-model.nix b/deployment/data-model.nix
index 8f584af4..167e3c21 100644
--- a/deployment/data-model.nix
+++ b/deployment/data-model.nix
@@ -15,11 +15,13 @@ let
     ;
 
   functionType = import ./function.nix;
-  application-resources = {
+  application-resources = submodule {
     options.resources = mkOption {
       # TODO: maybe transpose, and group the resources by type instead
       type = attrsOf (
-        attrTag (lib.mapAttrs (_name: resource: mkOption { type = resource.request; }) config.resources)
+        attrTag (
+          lib.mapAttrs (_name: resource: mkOption { type = submodule resource.request; }) config.resources
+        )
       );
     };
   };
@@ -52,12 +54,13 @@ in
               readOnly = true;
               default = input: (application.config.implementation input).output;
             };
+            # TODO(@fricklerhandwerk): this needs a better name, it's just the type
             config-mapping = mkOption {
               description = "Function type for the mapping from application configuration to required resources";
               type = submodule functionType;
               readOnly = true;
               default = {
-                input-type = application.config.module;
+                input-type = submodule application.config.module;
                 output-type = application-resources;
               };
             };
diff --git a/deployment/function.nix b/deployment/function.nix
index d1a047f0..f0210a34 100644
--- a/deployment/function.nix
+++ b/deployment/function.nix
@@ -5,7 +5,6 @@
 let
   inherit (lib) mkOption types;
   inherit (types)
-    deferredModule
     submodule
     functionTo
     optionType
@@ -14,10 +13,10 @@ in
 {
   options = {
     input-type = mkOption {
-      type = deferredModule;
+      type = optionType;
     };
     output-type = mkOption {
-      type = deferredModule;
+      type = optionType;
     };
     function-type = mkOption {
       type = optionType;
@@ -25,10 +24,10 @@ in
       default = functionTo (submodule {
         options = {
           input = mkOption {
-            type = submodule config.input-type;
+            type = config.input-type;
           };
           output = mkOption {
-            type = submodule config.output-type;
+            type = config.output-type;
           };
         };
       });