diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index a74d00164180..24d3022a011d 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -37522,7 +37522,11 @@ with pkgs;
 
   enlightenment = recurseIntoAttrs (callPackage ../desktops/enlightenment { });
 
-  expidus = recurseIntoAttrs (callPackage ../desktops/expidus {});
+  expidus = recurseIntoAttrs (callPackages ../desktops/expidus {
+    # Use the Nix built Flutter Engine for testing.
+    # Also needed when we eventually package Genesis Shell.
+    flutterPackages = flutterPackages-source;
+  });
 
   gnome2 = recurseIntoAttrs (callPackage ../desktops/gnome-2 { });