diff --git a/contracts/Ojo.sol b/contracts/Ojo.sol
index 97c1f23..fe4c147 100644
--- a/contracts/Ojo.sol
+++ b/contracts/Ojo.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.20;
 
-import "@axelar-network/axelar-gmp-sdk-solidity/contracts/executable/AxelarExecutable.sol";
+import "@axelar-network/axelar-gmp-sdk-solidity/contracts/express/AxelarExpressExecutable.sol";
 import "@axelar-network/axelar-gmp-sdk-solidity/contracts/interfaces/IAxelarGateway.sol";
 import "@axelar-network/axelar-gmp-sdk-solidity/contracts/interfaces/IAxelarGasService.sol";
 import "@axelar-network/axelar-gmp-sdk-solidity/contracts/interfaces/IERC20.sol";
@@ -9,7 +9,7 @@ import "@axelar-network/axelar-gmp-sdk-solidity/contracts/upgradable/Upgradable.
 import "./IOjo.sol";
 import "./OjoTypes.sol";
 
-contract Ojo is IOjo, AxelarExecutable, Upgradable {
+contract Ojo is IOjo, AxelarExpressExecutable, Upgradable {
     IAxelarGasService public immutable gasReceiver;
 
     string public ojoChain;
@@ -24,7 +24,7 @@ contract Ojo is IOjo, AxelarExecutable, Upgradable {
 
     error AlreadyInitialized();
 
-    constructor(address gateway_, address gasReceiver_) AxelarExecutable(gateway_) {
+    constructor(address gateway_, address gasReceiver_) AxelarExpressExecutable(gateway_) {
         gasReceiver = IAxelarGasService(gasReceiver_);
     }
 
diff --git a/testnet_chains.json b/testnet_chains.json
index 4796e55..8e3df94 100644
--- a/testnet_chains.json
+++ b/testnet_chains.json
@@ -76,6 +76,13 @@
         "rpc": "https://optimism-goerli.infura.io/v3/9aa3d95b3bc440fa88ea12eaa4456161",
         "tokenSymbol": "ETH"
     },
+    {
+        "name": "Optimism Sepolia",
+        "chainId": 11155420,
+        "gateway": "0xe432150cce91c13a887f7D836923d5597adD8E31",
+        "rpc": "https://sepolia.optimism.io",
+        "tokenSymbol": "ETH"
+    },
     {
         "name": "Base Goerli",
         "chainId": 84531,
@@ -83,6 +90,13 @@
         "rpc": "https://goerli.base.org",
         "tokenSymbol": "ETH"
     },
+    {
+        "name": "Base Sepolia",
+        "chainId": 84532,
+        "gateway": "0xe432150cce91c13a887f7D836923d5597adD8E31",
+        "rpc": "https://base-sepolia-rpc.publicnode.com",
+        "tokenSymbol": "ETH"
+    },
     {
         "name": "Mantle",
         "chainId": 5001,