diff --git a/version.go b/version.go
index 08f70c9..335239c 100644
--- a/version.go
+++ b/version.go
@@ -19,4 +19,4 @@
 package grpc
 
 // Version is the current grpc version.
-const Version = "1.21.4"
+const Version = "1.21.5-dev"