diff --git a/src/midi_Defs.h b/src/midi_Defs.h
index 16ca1f2..4c36b13 100644
--- a/src/midi_Defs.h
+++ b/src/midi_Defs.h
@@ -39,6 +39,11 @@ typedef uint8_t byte;
 
 BEGIN_MIDI_NAMESPACE
 
+#define MIDI_LIBRARY_VERSION        0x040300
+#define MIDI_LIBRARY_VERSION_MAJOR  4
+#define MIDI_LIBRARY_VERSION_MINOR  3
+#define MIDI_LIBRARY_VERSION_PATCH  0
+
 // -----------------------------------------------------------------------------
 
 #define MIDI_CHANNEL_OMNI       0