diff --git a/include/libultraship/libultra/types.h b/include/libultraship/libultra/types.h
index 7d9b4ac04dd..0a36c28d9e9 100644
--- a/include/libultraship/libultra/types.h
+++ b/include/libultraship/libultra/types.h
@@ -3,6 +3,7 @@
 
 #include <stdint.h>
 #include <stddef.h>
+#include <stdbool.h>
 
 typedef signed char s8;
 typedef unsigned char u8;