diff --git a/nixos/tests/leaps.nix b/nixos/tests/leaps.nix
index ac0c602d445..ec5b69a7629 100644
--- a/nixos/tests/leaps.nix
+++ b/nixos/tests/leaps.nix
@@ -26,7 +26,7 @@ import ./make-test-python.nix ({ pkgs,  ... }:
       server.wait_for_open_port(6666)
       client.wait_for_unit("network.target")
       assert "leaps" in client.succeed(
-          "${pkgs.curl}/bin/curl http://server:6666/leaps/"
+          "${pkgs.curl}/bin/curl -f http://server:6666/leaps/"
       )
     '';
 })