diff --git a/proto/payment_processing.thrift b/proto/payment_processing.thrift
index 5daf629..b44ff9f 100644
--- a/proto/payment_processing.thrift
+++ b/proto/payment_processing.thrift
@@ -337,6 +337,7 @@ struct ShopParams {
     2: required domain.ShopDetails details
     3: required domain.ContractID contract_id
     4: required domain.PayoutToolID payout_tool_id
+    5: optional domain.Proxy proxy
 }
 
 struct ContractParams {