diff --git a/packaging/hydra.nix b/packaging/hydra.nix
index 664ee18ca..6df878239 100644
--- a/packaging/hydra.nix
+++ b/packaging/hydra.nix
@@ -187,6 +187,19 @@ in
           pkgs = nixpkgsFor.${system}.native;
         }
       );
+
+      nixpkgsLibTestsLazy = forAllSystems (
+        system:
+        lib.overrideDerivation
+          (import (nixpkgs + "/lib/tests/test-with-nix.nix") {
+            lib = nixpkgsFor.${system}.native.lib;
+            nix = self.packages.${system}.nix-cli;
+            pkgs = nixpkgsFor.${system}.native;
+          })
+          (_: {
+            "NIX_CONFIG" = "lazy-trees = true";
+          })
+      );
     };
 
   metrics.nixpkgs = import "${nixpkgs-regression}/pkgs/top-level/metrics.nix" {