Layerzero DVN Blueprint Template 🌐

A template for creating Decentralized Verifier Network (DVN) Blueprints for LayerZero V2 on Tangle

📚 Overview

This project provides a template for creating Layerzero Decentralized Verifier Network (DVN) Blueprints on the Tangle Network. DVNs are an essential component of the LayerZero protocol, responsible for verifying cross-chain messages and ensuring the security and reliability of inter-blockchain communications.

Blueprints in Tangle are specifications for Actively Validated Services (AVS) that run arbitrary computations for a user-specified period of time. This template allows developers to create reusable DVN infrastructures, enabling them to participate in the LayerZero ecosystem and potentially monetize their work.

📚 Prerequisites

Before you can run this project, you will need to have the following software installed on your machine:

• Rust
• Forge
• Tangle

You will also need to install cargo-tangle, our CLI tool for creating and deploying Tangle Blueprints:

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/tangle-network/gadget/releases/download/cargo-tangle-v0.1.2/cargo-tangle-installer.sh | sh

Or, if you prefer to install the CLI from crates.io:

cargo install cargo-tangle --force # to get the latest version

🛠️ Getting Started

1. Create a new project using the DVN blueprint template:

cargo tangle blueprint create --name my-dvn-blueprint --repo https://github.com/tangle-network/layerzero-dvn-blueprint-template

2. Navigate to your project directory:

cd my-dvn-blueprint

3. Implement your offchain DVN logic in src/lib.rs and onchain DVN in contracts/src/, building upon the provided template functions.

4. Build your project:

cargo build

5. Deploy your DVN blueprint to the Tangle network:

cargo tangle blueprint deploy

📖 Understanding the Template

The DVN has one off-chain workflow:

1. The DVN first listens for the PacketSent event:
2. After the PacketSent event, the DVNFeePaid is how you know your DVN has been assigned to verify the packet's payloadHash.
3. After receiving the fee, your DVN should query the address of the MessageLib on the destination chain:
4. After your DVN has retrieved the receive MessageLib, you should read the MessageLib configuration from it. In the configuration is the required block confirmations to wait before calling verify on the destination chain.
5. Your DVN should next do an idempotency check:
   1. If the state is true, then your idempotency check indicates that you already verified this packet. You can terminate your DVN workflow.
   2. If the state is false, then you must call ULN.verify:

📚 Resources

• LayerZero V2 Documentation
• Tangle Network Documentation

📬 Feedback

If you have any feedback or issues, please feel free to open an issue on our GitHub repository.

📜 License

This project is licensed under the MIT License. See the LICENSE file for more details.