diff --git a/config/config_test.go b/config/config_test.go
index 5b65db44..2c6b9bd1 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -149,6 +149,8 @@ badconfig:
 
 func TestParseAndValidateConfigBytesWithAlerting(t *testing.T) {
 	config, err := parseAndValidateConfigBytes([]byte(`
+debug: true
+
 alerting:
   slack:
     webhook-url: "http://example.com"