diff --git a/modules/aspects/provides/flake-parts/inputs.nix b/modules/aspects/provides/flake-parts/inputs.nix
index d12362f9..cca051d4 100644
--- a/modules/aspects/provides/flake-parts/inputs.nix
+++ b/modules/aspects/provides/flake-parts/inputs.nix
@@ -48,7 +48,9 @@ let
       user,
       host,
     }:
-    lib.mkMerge (map (c: mkAspect c host.system) user.classes);
+    {
+      includes = map (c: mkAspect c host.system) user.classes;
+    };
 
   hmAspect = { home }: mkAspect home.class home.system;
 
diff --git a/modules/aspects/provides/flake-parts/self.nix b/modules/aspects/provides/flake-parts/self.nix
index 6f491a97..6a48f2d0 100644
--- a/modules/aspects/provides/flake-parts/self.nix
+++ b/modules/aspects/provides/flake-parts/self.nix
@@ -48,7 +48,9 @@ let
       user,
       host,
     }:
-    lib.mkMerge (map (c: mkAspect c host.system) user.classes);
+    {
+      includes = map (c: mkAspect c host.system) user.classes;
+    };
 
   homeAspect = { home }: mkAspect home.class home.system;
 in
diff --git a/templates/ci/modules/features/deadbugs/issue-369-namespace-system-scoped-inputs.nix b/templates/ci/modules/features/deadbugs/issue-369-namespace-system-scoped-inputs.nix
new file mode 100644
index 00000000..3e671239
--- /dev/null
+++ b/templates/ci/modules/features/deadbugs/issue-369-namespace-system-scoped-inputs.nix
@@ -0,0 +1,94 @@
+{ denTest, ... }:
+{
+  flake.tests.deadbugs-issue-369 = {
+
+    test-self-arg-includes = denTest (
+      {
+        den,
+        lib,
+        inputs,
+        tuxHm,
+        ...
+      }:
+      {
+        den.hosts.x86_64-linux.igloo.users.tux = { };
+        den.default.homeManager.home.stateVersion = "25.11";
+
+        den.default.includes = [ den._.self' ];
+        den.aspects.tux.includes = [ den.aspects.hola ];
+
+        den.aspects.hola.homeManager =
+          { self', ... }@args:
+          {
+            home.sessionVariables.FOO = lib.getName self'.legacyPackages.hello;
+          };
+
+        expr = tuxHm.home.sessionVariables.FOO;
+        expected = "hello";
+      }
+    );
+
+    test-inputs-arg-includes = denTest (
+      {
+        den,
+        lib,
+        inputs,
+        tuxHm,
+        ...
+      }:
+      {
+        den.hosts.x86_64-linux.igloo.users.tux = { };
+        den.default.homeManager.home.stateVersion = "25.11";
+
+        den.default.includes = [ den._.inputs' ];
+        den.aspects.tux.includes = [ den.aspects.hola ];
+
+        den.aspects.hola.homeManager =
+          { inputs', ... }@args:
+          {
+            home.sessionVariables.FOO = lib.getName inputs'.nixpkgs.legacyPackages.hello;
+          };
+
+        expr = tuxHm.home.sessionVariables.FOO;
+        expected = "hello";
+      }
+    );
+
+    test-everything-includes = denTest (
+      {
+        den,
+        lib,
+        igloo,
+        inputs,
+        gloom,
+        __findFile,
+        tuxHm,
+        ...
+      }:
+      {
+        imports = [ (inputs.den.namespace "gloom" false) ];
+        _module.args.__findFile = den.lib.__findFile;
+
+        den.hosts.x86_64-linux.igloo.users.tux = { };
+        den.default.homeManager.home.stateVersion = "25.11";
+
+        den.default.includes = [
+          den._.inputs'
+          den._.define-user
+        ];
+        den.aspects.tux.includes = [ gloom.everywhere ];
+        gloom.everywhere.includes = [ <gloom/apps/helix> ];
+
+        gloom.apps.provides.helix.homeManager =
+          { inputs', ... }@args:
+          {
+            home.packages = [ inputs'.nixpkgs.legacyPackages.hello ];
+          };
+
+        expr = builtins.elem "hello" (map lib.getName tuxHm.home.packages);
+        expected = true;
+      }
+    );
+
+  };
+}
diff --git a/templates/ci/modules/test-support/eval-den.nix b/templates/ci/modules/test-support/eval-den.nix
index 47bad3fd..8c107259 100644
--- a/templates/ci/modules/test-support/eval-den.nix
+++ b/templates/ci/modules/test-support/eval-den.nix
@@ -9,12 +9,15 @@ let
     inherit ((evalDen module).config) expr expected;
   };
 
-  # fake-parts
+  # emulate fake-parts only for self and nixpkgs.
   withSystem =
     system:
     let
-      inputs' = builtins.mapAttrs (_: builtins.mapAttrs (_: value: value.${system})) inputs;
-      self'.packages.hello = inputs.nixpkgs.legacyPackages.${system}.hello;
+      pkgs = inputs.nixpkgs.legacyPackages.${system};
+      inputs'.nixpkgs.packages = pkgs;
+      inputs'.nixpkgs.legacyPackages = pkgs;
+      self'.packages = pkgs;
+      self'.legacyPackages = pkgs;
     in
     cb: cb { inherit inputs' self'; };