diff --git a/safeptr.go b/safeptr.go
index 1139fea4..5c1d264a 100644
--- a/safeptr.go
+++ b/safeptr.go
@@ -1,5 +1,5 @@
-//go:build go1.21
-// +build go1.21
+//go:build go1.18
+// +build go1.18
 
 /*
 Copyright 2023 The Kubernetes Authors.
diff --git a/safeptr_test.go b/safeptr_test.go
index b1d91a54..29e03c39 100644
--- a/safeptr_test.go
+++ b/safeptr_test.go
@@ -1,5 +1,5 @@
-//go:build go1.21
-// +build go1.21
+//go:build go1.18
+// +build go1.18
 
 /*
 Copyright 2023 The Kubernetes Authors.