diff --git a/signature/fulcio_cert.go b/signature/fulcio_cert.go
index 3049becf30..a68831542c 100644
--- a/signature/fulcio_cert.go
+++ b/signature/fulcio_cert.go
@@ -1,3 +1,6 @@
+//go:build !containers_image_fulcio_stub
+// +build !containers_image_fulcio_stub
+
 package signature
 
 import (