diff --git a/include/tkey/touch.h b/include/tkey/touch.h
index dc95236..ca76f79 100644
--- a/include/tkey/touch.h
+++ b/include/tkey/touch.h
@@ -6,6 +6,7 @@
 #ifndef TKEY_TOUCH_H
 #define TKEY_TOUCH_H
 
+#include <stdbool.h>
 #include <stdint.h>
 #include <tkey/tk1_mem.h>