diff --git a/clatd.h b/clatd.h
index 00a4094..3459b09 100644
--- a/clatd.h
+++ b/clatd.h
@@ -22,6 +22,7 @@
 
 #define MAXMTU 1500
 #define PACKETLEN (MAXMTU+sizeof(struct tun_pi))
+#define CLATD_VERSION "1.1"
 
 // how frequently (in seconds) to poll for an address change while traffic is passing
 #define INTERFACE_POLL_FREQUENCY 30