diff --git a/sofort/tools/pkgconf.sh b/sofort/tools/pkgconf.sh
index a37e368..614fdec 100755
--- a/sofort/tools/pkgconf.sh
+++ b/sofort/tools/pkgconf.sh
@@ -1,5 +1,7 @@
 #!/bin/sh
 
+set -eu
+
 # prefix, exec_prefix
 if [ "$PKGCONF_PREFIX" = "$PKGCONF_EXEC_PREFIX" ]; then
 	pkgconf_prefix="${PKGCONF_PREFIX}"