diff --git a/proto/metadata.proto b/proto/metadata.proto
index 618a5f2..8175ec6 100644
--- a/proto/metadata.proto
+++ b/proto/metadata.proto
@@ -211,4 +211,5 @@ message Metadata {
     optional string thumbnail = 9;
     optional string preview = 10;
     optional string licenseUrl = 11;
+    optional sint64 releaseTime = 12;
 }