diff --git a/include/System/object.h b/include/System/object.h
index eb8f918..6cbc031 100644
--- a/include/System/object.h
+++ b/include/System/object.h
@@ -18,6 +18,8 @@
 #ifndef LIBSYSTEM_SYSTEM_OBJECT_H
 # define LIBSYSTEM_SYSTEM_OBJECT_H
 
+# include <sys/types.h>
+
 
 /* Object */
 typedef void Object;