diff --git a/pkgs/test/haskell/upstreamStackHpackVersion/default.nix b/pkgs/test/haskell/upstreamStackHpackVersion/default.nix
index 788a3e2db5ef..4e01c213700b 100644
--- a/pkgs/test/haskell/upstreamStackHpackVersion/default.nix
+++ b/pkgs/test/haskell/upstreamStackHpackVersion/default.nix
@@ -46,7 +46,7 @@ let
       --retry 3
       --disable-epsv
       --cookie-jar cookies
-      --user-agent "curl "
+      --user-agent "nixpkgs stack version test/1.0"
       --insecure
     )