diff --git a/lib/introspection/default.nix b/lib/introspection/default.nix
index a3cef0f6f..a7aebeafe 100644
--- a/lib/introspection/default.nix
+++ b/lib/introspection/default.nix
@@ -10,6 +10,46 @@ let
     ]
   );
 
+  pushPositions = map (
+    def:
+    lib.mapAttrs (_n: v: {
+      inherit (def) file;
+      value = v;
+    }) def.value
+  );
+
+  unwrapNullOr =
+    type:
+    let
+      typeName = type.name or null;
+    in
+    if typeName == "nullOr" then type.nestedTypes.name or null else typeName;
+
+  mergeAttrs =
+    { type, definitionsWithLocations }:
+    let
+      # Vendored merge from lib.types.attrsOf
+      # Because we still cannot access highest prio for the individual attrs yet.
+      elemType = type.nestedTypes.elemType;
+      mergedAttrs = lib.zipAttrsWith (name: defs: lib.modules.mergeDefinitions ([ name ]) elemType defs) (
+        pushPositions definitionsWithLocations
+      );
+      headType = unwrapNullOr elemType;
+      nullable = elemType.name or null == "nullOr";
+      total = elemType.name or null == "submodule";
+    in
+    lib.mapAttrs (_name: merged: {
+      __this = {
+        prio = merged.defsFinal'.highestPrio;
+        files = map (def: def.file) merged.defsFinal'.values;
+        inherit
+          headType
+          nullable
+          total
+          ;
+      };
+    }) mergedAttrs;
+
   /**
     Takes a set of options as returned by `configuration`
 
@@ -45,19 +85,15 @@ let
     lib.mapAttrs (
       _: opt:
       let
-        headType =
-          let
-            typeName = opt.type.name or null;
-          in
-          if typeName == "nullOr" then opt.type.nestedTypes.name or null else typeName;
+        headType = unwrapNullOr opt.type;
         nullable = opt.type.name or null == "nullOr";
+        total = opt.type.name or null == "submodule";
 
         definitionInfo = {
           __this = {
             prio = opt.highestPrio or null;
             files = opt.files or [ ];
-            inherit headType nullable;
-            total = opt.type.name or null == "submodule";
+            inherit headType nullable total;
           };
         };
 
@@ -71,18 +107,34 @@ let
         /**
           Maps attrsOf and lazyAttrsOf
         */
-        handleAttrsOf = attrs: lib.mapAttrs (_: handleMeta) attrs;
+        handleAttrsOf =
+          type: defs: attrs:
+          lib.mapAttrs (
+            name: meta:
+            (mergeAttrs {
+              inherit type;
+              definitionsWithLocations = defs;
+            }).${name}
+            // handleMeta {
+              inherit meta;
+              definitionsWithLocations =
+                (builtins.zipAttrsWith (_name: values: values) (pushPositions defs)).${name};
+            }
+          ) attrs;
 
         /**
           Maps attrsOf and lazyAttrsOf
         */
-        handleListOf = list: { __list = lib.map handleMeta list; };
+        handleListOf = list: { __list = lib.map handleMeta { meta = list; }; };
 
         /**
           Unwraps the valueMeta of an option based on its type
         */
         handleMeta =
-          meta:
+          {
+            meta,
+            definitionsWithLocations ? [ ],
+          }:
           let
             hasType = meta ? _internal.type;
             type = meta._internal.type;
@@ -93,7 +145,7 @@ let
             # TODO: handle types
             getPrios { options = filterOptions meta.configuration.options; }
           else if type.name == "attrsOf" || type.name == "lazyAttrsOf" then
-            handleAttrsOf meta.attrs
+            handleAttrsOf meta._internal.type definitionsWithLocations meta.attrs
           # TODO: Add index support in nixpkgs first
           # else if type.name == "listOf" then
           #   handleListOf meta.list
@@ -103,7 +155,7 @@ let
       if opt ? type && opt.type.name == "submodule" then
         (definitionInfo) // submodulePrios
       else if opt ? type && (opt.type.name == "attrsOf" || opt.type.name == "lazyAttrsOf") then
-        definitionInfo // (handleAttrsOf opt.valueMeta.attrs)
+        definitionInfo // (handleAttrsOf opt.type opt.definitionsWithLocations opt.valueMeta.attrs)
       # TODO: Add index support in nixpkgs, otherwise we cannot
       else if opt ? type && (opt.type.name == "listOf") then
         definitionInfo // (handleListOf opt.valueMeta.list)
diff --git a/lib/introspection/test.nix b/lib/introspection/test.nix
index f04ca51a0..36fe58e6c 100644
--- a/lib/introspection/test.nix
+++ b/lib/introspection/test.nix
@@ -314,12 +314,17 @@ in
               }
             );
           };
+        }
+        {
+          config.foo.nested = lib.mkForce {
+            # <- 50 prio
+            "bar" = 2;
+          };
+        }
+        {
           config.foo = {
-            "nested" = {
-              "bar" = 2; # <- 100 prio ?
-            };
-            "other" = {
-              "bar" = lib.mkForce 2; # <- 50 prio ?
+            "other" = lib.mkForce {
+              "bar" = 2; # <- 50 prio
             };
           };
         }
@@ -330,11 +335,19 @@ in
       expected = {
         foo = {
           __this = {
-            files = [ "<unknown-file>" ];
+            files = [
+              "<unknown-file>"
+              "<unknown-file>"
+            ];
             prio = 100;
             total = false;
           };
           nested = {
+            __this = {
+              files = [ "<unknown-file>" ];
+              prio = 50;
+              total = true;
+            };
             bar = {
               __this = {
                 files = [ "<unknown-file>" ];
@@ -344,10 +357,15 @@ in
             };
           };
           other = {
+            __this = {
+              files = [ "<unknown-file>" ];
+              prio = 50;
+              total = true;
+            };
             bar = {
               __this = {
                 files = [ "<unknown-file>" ];
-                prio = 50;
+                prio = 100;
                 total = false;
               };
             };
@@ -401,7 +419,17 @@ in
             total = false;
           };
           a = {
+            __this = {
+              files = [ "<unknown-file>" ];
+              prio = 100;
+              total = false;
+            };
             b = {
+              __this = {
+                files = [ "<unknown-file>" ];
+                prio = 100;
+                total = true;
+              };
               bar = {
                 __this = {
                   files = [ "<unknown-file>" ];
@@ -411,6 +439,11 @@ in
               };
             };
             c = {
+              __this = {
+                files = [ "<unknown-file>" ];
+                prio = 100;
+                total = true;
+              };
               bar = {
                 __this = {
                   files = [ "<unknown-file>" ];
@@ -421,7 +454,17 @@ in
             };
           };
           x = {
+            __this = {
+              files = [ "<unknown-file>" ];
+              prio = 100;
+              total = false;
+            };
             y = {
+              __this = {
+                files = [ "<unknown-file>" ];
+                prio = 100;
+                total = true;
+              };
               bar = {
                 __this = {
                   files = [ "<unknown-file>" ];
@@ -431,6 +474,11 @@ in
               };
             };
             z = {
+              __this = {
+                files = [ "<unknown-file>" ];
+                prio = 100;
+                total = true;
+              };
               bar = {
                 __this = {
                   files = [ "<unknown-file>" ];
@@ -443,7 +491,6 @@ in
         };
       };
     };
-
   test_attrsOf_submodule_default =
     let
       evaluated = eval [
@@ -496,6 +543,14 @@ in
             total = false;
           };
           jon = {
+            __this = {
+              files = [
+                "<unknown-file>"
+                "inventory.json"
+              ];
+              prio = 100;
+              total = true;
+            };
             fludl = {
               __this = {
                 files = [ "<unknown-file>" ];