diff --git a/rpc_util.go b/rpc_util.go
index 66d34eb9..96c790be 100644
--- a/rpc_util.go
+++ b/rpc_util.go
@@ -442,3 +442,11 @@ func backoff(retries int) (t time.Duration) {
 	}
 	return time.Duration(backoff)
 }
+
+// SupportPackageIsVersion1 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the grpc package.
+//
+// This constant may be renamed in the future if a change in the generated code
+// requires a synchronised update of grpc-go and protoc-gen-go. This constant
+// should not be referenced from any other code.
+const SupportPackageIsVersion1 = true