diff --git a/cpld.hpp b/cpld.hpp
index 01550fe..bfb09ba 100644
--- a/cpld.hpp
+++ b/cpld.hpp
@@ -1,5 +1,7 @@
 #pragma once
 
+#include "handler.hpp"
+
 #include <ipmid/api.h>
 
 namespace google
@@ -9,7 +11,8 @@
 
 // Given a cpld identifier, return a version if available.
 ipmi_ret_t CpldVersion(const uint8_t* reqBuf, uint8_t* replyBuf,
-                       size_t* dataLen);
+                       size_t* dataLen,
+                       const HandlerInterface* handler = &handlerImpl);
 
 } // namespace ipmi
 } // namespace google