diff --git a/external/ircolib/types.hpp b/external/ircolib/types.hpp
index c3e0c41..728b9e6 100644
--- a/external/ircolib/types.hpp
+++ b/external/ircolib/types.hpp
@@ -1,5 +1,6 @@
 #pragma once
 #include <cstdint>
+#include <cstddef>
 
 namespace ircolib {
 using u8 = uint8_t;