diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 91cbaa336c9c2816fc2c9168ec8bfd94f97c97d3..ae66714013e215f9f4c4ca6022e33528449bd848 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -26,7 +26,7 @@ unit-tests:
   script:
     - |
       # GRID is set in one of the "instantiations" of this job template.
-      nix-shell --run "morph build morph/grid/${GRID}/grid.nix"
+      nix-shell --run "morph build --show-trace morph/grid/${GRID}/grid.nix"
 
 
 morph-build-localdev: