diff --git a/proto/common.proto b/proto/common.proto
index 50244d3..6aae674 100644
--- a/proto/common.proto
+++ b/proto/common.proto
@@ -355,6 +355,9 @@ enum ChainRef {
   CHAIN_AZTEC__TESTNET = 10186;
   CHAIN_AZTEC__DEVNET = 10187;
   CHAIN_MOCA__TESTNET = 10188;
+
+  // Virtual chains (no real blockchain)
+  CHAIN_LAMBDA__VIRTUAL = 99999; // P2P Lambda REST API synthetic provider
 }
 
 message SingleAddress {