diff --git a/sources/Coturn_config_rotate.sh b/sources/Coturn_config_rotate.sh
index bc3945e..e036579 100644
--- a/sources/Coturn_config_rotate.sh
+++ b/sources/Coturn_config_rotate.sh
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+set -eu
+
 app_instance=__APP__
 
 source /usr/share/yunohost/helpers
diff --git a/sources/update_synapse_for_appservice.sh b/sources/update_synapse_for_appservice.sh
index 428e843..bf6979c 100644
--- a/sources/update_synapse_for_appservice.sh
+++ b/sources/update_synapse_for_appservice.sh
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+set -eu
+
 app=__APP__
 service_config_file=/etc/matrix-$app/conf.d/app_service.yaml