diff --git a/common/buf/readv_reader_wasm.go b/common/buf/readv_reader_wasm.go
index 4b775bc6a..a4d9fa677 100644
--- a/common/buf/readv_reader_wasm.go
+++ b/common/buf/readv_reader_wasm.go
@@ -1,3 +1,5 @@
+// +build wasm
+
 package buf
 
 import (