diff --git a/src/testing/bridges/ArbitrumBridgeTesting.sol b/src/testing/bridges/ArbitrumBridgeTesting.sol
index 13adfa8..b6e8a3c 100644
--- a/src/testing/bridges/ArbitrumBridgeTesting.sol
+++ b/src/testing/bridges/ArbitrumBridgeTesting.sol
@@ -6,6 +6,7 @@ import { Vm }        from "forge-std/Vm.sol";
 import { Bridge }                from "../Bridge.sol";
 import { Domain, DomainHelpers } from "../Domain.sol";
 import { RecordedLogs }          from "../utils/RecordedLogs.sol";
+import { ArbitrumForwarder }     from "../../forwarders/ArbitrumForwarder.sol";
 
 interface InboxLike {
     function createRetryableTicket(
@@ -80,9 +81,9 @@ library ArbitrumBridgeTesting {
 
         bytes32 name = keccak256(bytes(destinationChainAlias));
         if (name == keccak256("arbitrum_one")) {
-            sourceCrossChainMessenger = 0x4Dbd4fc535Ac27206064B68FfCf827b0A60BAB3f;
+            sourceCrossChainMessenger = ArbitrumForwarder.L1_CROSS_DOMAIN_ARBITRUM_ONE;
         } else if (name == keccak256("arbitrum_nova")) {
-            sourceCrossChainMessenger = 0xc4448b71118c9071Bcb9734A0EAc55D18A153949;
+            sourceCrossChainMessenger = ArbitrumForwarder.L1_CROSS_DOMAIN_ARBITRUM_NOVA;
         } else {
             revert("Unsupported destination chain");
         }
diff --git a/src/testing/bridges/CCTPBridgeTesting.sol b/src/testing/bridges/CCTPBridgeTesting.sol
index 5a90714..7757f17 100644
--- a/src/testing/bridges/CCTPBridgeTesting.sol
+++ b/src/testing/bridges/CCTPBridgeTesting.sol
@@ -6,6 +6,7 @@ import { Vm }        from "forge-std/Vm.sol";
 import { Bridge }                from "../Bridge.sol";
 import { Domain, DomainHelpers } from "../Domain.sol";
 import { RecordedLogs }          from "../utils/RecordedLogs.sol";
+import { CCTPForwarder }         from "../../forwarders/CCTPForwarder.sol";
 
 interface IMessenger {
     function receiveMessage(bytes calldata message, bytes calldata attestation) external returns (bool success);
@@ -35,17 +36,17 @@ library CCTPBridgeTesting {
     function getCircleMessengerFromChainAlias(string memory chainAlias) internal pure returns (address) {
         bytes32 name = keccak256(bytes(chainAlias));
         if (name == keccak256("mainnet")) {
-            return 0x0a992d191DEeC32aFe36203Ad87D7d289a738F81;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_ETHEREUM;
         } else if (name == keccak256("avalanche")) {
-            return 0x8186359aF5F57FbB40c6b14A588d2A59C0C29880;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_AVALANCHE;
         } else if (name == keccak256("optimism")) {
-            return 0x4D41f22c5a0e5c74090899E5a8Fb597a8842b3e8;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_OPTIMISM;
         } else if (name == keccak256("arbitrum_one")) {
-            return 0xC30362313FBBA5cf9163F0bb16a0e01f01A896ca;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_ARBITRUM_ONE;
         } else if (name == keccak256("base")) {
-            return 0xAD09780d193884d503182aD4588450C416D6F9D4;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_BASE;
         } else if (name == keccak256("polygon")) {
-            return 0xF3be9355363857F3e001be68856A2f96b4C39Ba9;
+            return CCTPForwarder.MESSAGE_TRANSMITTER_CIRCLE_POLYGON_POS;
         } else {
             revert("Unsupported chain");
         }
diff --git a/src/testing/bridges/OptimismBridgeTesting.sol b/src/testing/bridges/OptimismBridgeTesting.sol
index cc60044..bcc2009 100644
--- a/src/testing/bridges/OptimismBridgeTesting.sol
+++ b/src/testing/bridges/OptimismBridgeTesting.sol
@@ -6,6 +6,7 @@ import { Vm }        from "forge-std/Vm.sol";
 import { Bridge }                from "../Bridge.sol";
 import { Domain, DomainHelpers } from "../Domain.sol";
 import { RecordedLogs }          from "../utils/RecordedLogs.sol";
+import { OptimismForwarder }     from "../../forwarders/OptimismForwarder.sol";
 
 interface IMessenger {
     function sendMessage(
@@ -60,11 +61,11 @@ library OptimismBridgeTesting {
 
         bytes32 name = keccak256(bytes(destinationChainAlias));
         if (name == keccak256("optimism")) {
-            sourceCrossChainMessenger = 0x25ace71c97B33Cc4729CF772ae268934F7ab5fA1;
+            sourceCrossChainMessenger = OptimismForwarder.L1_CROSS_DOMAIN_OPTIMISM;
         } else if (name == keccak256("base")) {
-            sourceCrossChainMessenger = 0x866E82a600A1414e583f7F13623F1aC5d58b0Afa;
+            sourceCrossChainMessenger = OptimismForwarder.L1_CROSS_DOMAIN_BASE;
         } else if (name == keccak256("world_chain")) {
-            sourceCrossChainMessenger = 0xf931a81D18B1766d15695ffc7c1920a62b7e710a;
+            sourceCrossChainMessenger = OptimismForwarder.L1_CROSS_DOMAIN_WORLD_CHAIN;
         } else {
             revert("Unsupported destination chain");
         }