diff --git a/server/backtask/constant/constant.go b/server/backtask/constant/constant.go
index a729409f..f7903b92 100644
--- a/server/backtask/constant/constant.go
+++ b/server/backtask/constant/constant.go
@@ -16,4 +16,15 @@ const (
 	MAX_MODULE_IDX
 )
 
+const (
+	MAIL_HERO_MINT = "hero.mint"
+	MAIL_HERO_LOCK = "hero.lock"
+	MAIL_HERO_UNLOCK = "hero.unlock"
+
+	MAIL_GOLD_BULLION_MINT = "gold_bullion.mint"
+	MAIL_GOLD_BULLIONLOCK = "gold_bullion.lock"
+	MAIL_GOLD_BULLION_UNLOCK = "gold_bullion.unlock"
+
+)
+
 const BASE_SCORE = 2800