diff --git a/nixos/release.nix b/nixos/release.nix
index 1657dcf502d2..3307a3a67470 100644
--- a/nixos/release.nix
+++ b/nixos/release.nix
@@ -188,12 +188,15 @@ in rec {
 
   # Ensure that all packages used by the minimal NixOS config end up in the channel.
   dummy = forAllSystems (system: pkgs.runCommand "dummy"
-    { propagatedBuildInputs = (import lib/eval-config.nix {
+    { toplevel = (import lib/eval-config.nix {
         inherit system;
-        modules = lib.singleton ({ config, pkgs, ... }: { });
-      }).config.environment.systemPackages;
+        modules = lib.singleton ({ config, pkgs, ... }:
+          { fileSystems."/".device  = lib.mkDefault "/dev/sda1";
+            boot.loader.grub.device = lib.mkDefault "/dev/sda";
+          });
+      }).config.system.build.toplevel;
     }
-    "mkdir $out; fixupPhase");
+    "mkdir $out; ln -s $toplevel $out/dummy");
 
 
   # Provide a tarball that can be unpacked into an SD card, and easily