diff --git a/krebs/3modules/ci.nix b/krebs/3modules/ci.nix
index 4cfe598d6..62efce44b 100644
--- a/krebs/3modules/ci.nix
+++ b/krebs/3modules/ci.nix
@@ -26,6 +26,7 @@ let
 
   hostname = config.networking.hostName;
   getJobs = pkgs.writeDash "get_jobs" ''
+    set -efu
     nix-build --no-out-link --quiet -Q ./ci.nix > /dev/null
     nix-instantiate --quiet -Q --eval --strict --json ./ci.nix
   '';