diff --git a/nix/build-support/stacklock2nix/default.nix b/nix/build-support/stacklock2nix/default.nix
index ca981d2..4ea1432 100644
--- a/nix/build-support/stacklock2nix/default.nix
+++ b/nix/build-support/stacklock2nix/default.nix
@@ -520,6 +520,7 @@ let
           mkdir -p "$out"
           cd "$out"
           ${lib.concatMapStrings copyForPkg pkgs}
+          true
         '';
 
   # Similar to callHackage, but instead of internally running cabal2nix, it