diff --git a/osbase/build/mkcpio/main.go b/osbase/build/mkcpio/main.go
index 000a979..ab946d1 100644
--- a/osbase/build/mkcpio/main.go
+++ b/osbase/build/mkcpio/main.go
@@ -1,3 +1,6 @@
+// Copyright The Monogon Project Authors.
+// SPDX-License-Identifier: Apache-2.0
+
 package main
 
 import (