diff --git a/command_table.hpp b/command_table.hpp
index b51da9d..e882300 100644
--- a/command_table.hpp
+++ b/command_table.hpp
@@ -4,6 +4,7 @@
 
 #include <ipmid/api.h>
 
+#include <cstddef>
 #include <functional>
 #include <map>