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Version: Endpoint V2

Omnichain Applications (OApp)

Omnichain Apps (OApps), are smart contracts that you can deploy to pass generic messages between multiple blockchain ecosystems, creating an incredibly powerful contract standard for developers to build on top of.

In LayerZero, OApp's utilize generic message passing: the ability to send and receive arbitrary pieces of data seamlessly between contracts existing on different blockchain networks.

OApp Example OApp Example

Developers can add custom logic to these contracts to extend their functionality. This includes anything from specific financial logic in a DeFi application, to setting up a voting mechanism in a DAO, or even creating a cross-chain marketplace.

Contract Standard

LayerZero provides OApp for implementing generic message passing in your contracts.

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.22;

import "@layerzerolabs/contracts/OApp.sol";

contract MyOApp is OApp {
constructor(address _endpoint) OApp(_endpoint) {}

For installation, deployment, usage, and best practices, see the OApp Overview.