diff --git a/pkgs/overlays/cosmic-packages.nix b/pkgs/overlays/cosmic-packages.nix
index 9b9f6f5..5f34ffa 100644
--- a/pkgs/overlays/cosmic-packages.nix
+++ b/pkgs/overlays/cosmic-packages.nix
@@ -20,12 +20,11 @@ let
   };
 
   # Initialize pinned nixpkgs
-  futureNixpkgs = import futureNixpkgsSrc {
-    localSystem = self.stdenv.buildPlatform;
-    config = self.config;
-  } // (if self.stdenv.buildPlatform == self.stdenv.hostPlatform then {} else {
-    crossSystem = self.stdenv.hostPlatform;
-  });
+  futureNixpkgs = let
+    extended = self.extend (import ./unstable-from-source.nix {
+      unstableSource = futureNixpkgsSrc;
+    });
+  in extended.unstable;
 in
 
 import "${nixos-cosmic}/pkgs" {