diff --git a/contracts/bridges/optimism/IL1CrossDomainMessenger.sol b/contracts/bridges/optimism/IL1CrossDomainMessenger.sol
new file mode 100644
index 000000000..2658efdff
--- /dev/null
+++ b/contracts/bridges/optimism/IL1CrossDomainMessenger.sol
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.15;
+
+interface IL1CrossDomainMessenger {
+    event FailedRelayedMessage(bytes32 indexed msgHash);
+    event Initialized(uint8 version);
+    event RelayedMessage(bytes32 indexed msgHash);
+    event SentMessage(
+        address indexed target,
+        address sender,
+        bytes message,
+        uint256 messageNonce,
+        uint256 gasLimit
+    );
+    event SentMessageExtension1(address indexed sender, uint256 value);
+
+    function MESSAGE_VERSION() external view returns (uint16);
+
+    function MIN_GAS_CALLDATA_OVERHEAD() external view returns (uint64);
+
+    function MIN_GAS_DYNAMIC_OVERHEAD_DENOMINATOR()
+        external
+        view
+        returns (uint64);
+
+    function MIN_GAS_DYNAMIC_OVERHEAD_NUMERATOR()
+        external
+        view
+        returns (uint64);
+
+    function OTHER_MESSENGER() external view returns (address);
+
+    function PORTAL() external view returns (address);
+
+    function RELAY_CALL_OVERHEAD() external view returns (uint64);
+
+    function RELAY_CONSTANT_OVERHEAD() external view returns (uint64);
+
+    function RELAY_GAS_CHECK_BUFFER() external view returns (uint64);
+
+    function RELAY_RESERVED_GAS() external view returns (uint64);
+
+    function baseGas(bytes memory _message, uint32 _minGasLimit)
+        external
+        pure
+        returns (uint64);
+
+    function failedMessages(bytes32) external view returns (bool);
+
+    function initialize() external;
+
+    function messageNonce() external view returns (uint256);
+
+    function relayMessage(
+        uint256 _nonce,
+        address _sender,
+        address _target,
+        uint256 _value,
+        uint256 _minGasLimit,
+        bytes memory _message
+    ) external payable;
+
+    function sendMessage(
+        address _target,
+        bytes memory _message,
+        uint32 _minGasLimit
+    ) external payable;
+
+    function successfulMessages(bytes32) external view returns (bool);
+
+    function version() external view returns (string memory);
+
+    function xDomainMessageSender() external view returns (address);
+}
diff --git a/contracts/bridges/optimism/IL1StandardBridge.sol b/contracts/bridges/optimism/IL1StandardBridge.sol
new file mode 100644
index 000000000..72a98f1bd
--- /dev/null
+++ b/contracts/bridges/optimism/IL1StandardBridge.sol
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.15;
+
+interface IL1StandardBridge {
+    event ERC20BridgeFinalized(
+        address indexed localToken,
+        address indexed remoteToken,
+        address indexed from,
+        address to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ERC20BridgeInitiated(
+        address indexed localToken,
+        address indexed remoteToken,
+        address indexed from,
+        address to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ERC20DepositInitiated(
+        address indexed l1Token,
+        address indexed l2Token,
+        address indexed from,
+        address to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ERC20WithdrawalFinalized(
+        address indexed l1Token,
+        address indexed l2Token,
+        address indexed from,
+        address to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ETHBridgeFinalized(
+        address indexed from,
+        address indexed to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ETHBridgeInitiated(
+        address indexed from,
+        address indexed to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ETHDepositInitiated(
+        address indexed from,
+        address indexed to,
+        uint256 amount,
+        bytes extraData
+    );
+    event ETHWithdrawalFinalized(
+        address indexed from,
+        address indexed to,
+        uint256 amount,
+        bytes extraData
+    );
+
+    function MESSENGER() external view returns (address);
+
+    function OTHER_BRIDGE() external view returns (address);
+
+    function bridgeERC20(
+        address _localToken,
+        address _remoteToken,
+        uint256 _amount,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external;
+
+    function bridgeERC20To(
+        address _localToken,
+        address _remoteToken,
+        address _to,
+        uint256 _amount,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external;
+
+    function bridgeETH(uint32 _minGasLimit, bytes memory _extraData)
+        external
+        payable;
+
+    function bridgeETHTo(
+        address _to,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external payable;
+
+    function depositERC20(
+        address _l1Token,
+        address _l2Token,
+        uint256 _amount,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external;
+
+    function depositERC20To(
+        address _l1Token,
+        address _l2Token,
+        address _to,
+        uint256 _amount,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external;
+
+    function depositETH(uint32 _minGasLimit, bytes memory _extraData)
+        external
+        payable;
+
+    function depositETHTo(
+        address _to,
+        uint32 _minGasLimit,
+        bytes memory _extraData
+    ) external payable;
+
+    function deposits(address, address) external view returns (uint256);
+
+    function finalizeBridgeERC20(
+        address _localToken,
+        address _remoteToken,
+        address _from,
+        address _to,
+        uint256 _amount,
+        bytes memory _extraData
+    ) external;
+
+    function finalizeBridgeETH(
+        address _from,
+        address _to,
+        uint256 _amount,
+        bytes memory _extraData
+    ) external payable;
+
+    function finalizeERC20Withdrawal(
+        address _l1Token,
+        address _l2Token,
+        address _from,
+        address _to,
+        uint256 _amount,
+        bytes memory _extraData
+    ) external;
+
+    function finalizeETHWithdrawal(
+        address _from,
+        address _to,
+        uint256 _amount,
+        bytes memory _extraData
+    ) external payable;
+
+    function l2TokenBridge() external view returns (address);
+
+    function messenger() external view returns (address);
+
+    function version() external view returns (string memory);
+
+    receive() external payable;
+}