CCTP Relayer (old) - Noble to Solana & EVM
Note: This tool uses CCTP V1 (Legacy). Circle is deprecating V1 in favour of CCTP V2, with phase-out beginning July 2026. V1 remains fully functional until then, but a migration to V2 will be needed in the future.
A community-built tool for recovering and sending USDC transfers from Noble (Cosmos) using Circle's Cross-Chain Transfer Protocol (CCTP V1). Supports relaying to Solana and all major EVM chains: Ethereum, Avalanche, OP Mainnet, Arbitrum, Base, and Polygon PoS.
Buy me a coffee
This is an independent, community-built tool and is not affiliated with or endorsed by Circle, Solana, Phantom, MetaMask, or any other referenced project.
Live deployments
Features
- Recover transfers: Fetch Noble transaction details, extract the CCTP message, and relay to the destination chain
- Send USDC: Burn USDC on Noble and prepare a CCTP transfer to any supported destination
- Lookup pending transfers: Search for in-flight transfers by destination address
- Multi-chain support: Relay to Solana (Phantom) or any EVM chain (MetaMask / injected wallet)
- Auto-detection: Destination chain is detected automatically from the CCTP message
- Compute keccak256 message hash and fetch Circle attestation
- All fields are editable for power users
- External tool links for manual fallback
Usage
Recover a Transfer
- Enter your Noble transaction hash
- Click "Fetch TX" to retrieve the message data (the tool will auto-convert to hex, compute the hash, and fetch the attestation)
- Wait until the attestation status shows
complete
- The destination chain is detected automatically — connect the appropriate wallet:
- Solana: Connect Phantom wallet, then click "Relay to Solana"
- EVM chains: Connect MetaMask (or any injected wallet), then click "Relay to [Chain]"
Send USDC from Noble
- Connect your Keplr wallet
- Select the destination chain and enter the recipient address
- Enter the amount and send
Lookup Pending Transfers
Enter a destination address (Solana or EVM) to search for in-flight CCTP transfers waiting to be relayed.
Manual Entry
If you already have any intermediate values (message hash, attestation, etc.), you can paste them directly into the corresponding fields.
Project Structure
cctp-relayer/
├── api/ # Vercel serverless functions
│ ├── blockhash.js # GET /api/blockhash (proxies Solana RPC)
│ ├── config.js # Allowed origins config
│ └── relay.js # POST /api/relay (proxies Solana RPC)
├── public/ # Static website files
│ ├── app.js # Main application logic (all chains)
│ ├── index.html
│ └── styles.css
├── .github/workflows/ # CI/CD
│ └── deploy-gh-pages.yml # Auto-deploy to GitHub Pages
├── .gitignore
├── package.json
└── README.md
Hosting
Vercel (Recommended)
The API proxy keeps your Helius RPC key secret while allowing CORS from your domains.
- Push to GitHub
- Import repo at vercel.com
- Add environment variable:
HELIUS_RPC_URL = https://mainnet.helius-rpc.com/?api-key=YOUR_KEY
- Deploy
To update allowed origins, edit api/config.js and redeploy.
Local Testing
yarn install
yarn dev
Note: The /api/* proxy won't work locally (falls back to direct RPC).
GitHub Pages (Static only)
If you don't need the RPC proxy, you can host just the public/ folder on GitHub Pages. The app will fall back to the direct Solana RPC configured in the UI.
Configuration
All configuration values can be edited in the UI:
| Field | Default | Description |
|---|
| Noble LCD API | https://noble-api.polkachu.com | Noble REST API endpoint |
| Solana RPC | https://rpc.ankr.com/solana | Solana RPC endpoint (fallback) |
| Circle Attestation API | https://iris-api.circle.com/v1/attestations | Circle's attestation service |
| MessageTransmitter | CCTPmbSD7gX1bxKPAmg77w8oFzNFpaQiQUWD43TKaecd | Solana CCTP program |
| TokenMessengerMinter | CCTPiPYPc6AsJuwueEnWgSgucamXDZwBd53dQ11YiKX3 | Solana CCTP program |
EVM chain contract addresses (MessageTransmitter, TokenMessenger) are auto-configured based on the selected destination chain.
Domain IDs
| Chain | Domain ID |
|---|
| Ethereum | 0 |
| Avalanche | 1 |
| OP Mainnet | 2 |
| Arbitrum | 3 |
| Noble | 4 |
| Solana | 5 |
| Base | 6 |
| Polygon PoS | 7 |
Manual Fallback Tools
If any step in the UI fails, you can use these external tools:
Source Transaction
Attestation
Relay
Troubleshooting
CORS Issues
If the Circle attestation API fails due to CORS, you can:
- Manually fetch the attestation:
curl https://iris-api.circle.com/v1/attestations/{hash}
- Paste the attestation value directly into the UI
Transaction Simulation Failed
Check that:
- The attestation status is "complete"
- The message hasn't already been relayed (nonce already used)
- Your wallet has enough native tokens for gas (SOL for Solana, ETH for Ethereum/Base/Arbitrum/OP, MATIC for Polygon, AVAX for Avalanche)
- For EVM relays, your wallet is connected to the correct network (the app will prompt to switch)
Message Not Found in Transaction
The transaction may use a different event format. Check the browser console for the raw transaction events and manually extract the message.
Technical Details
Message Format
CCTP messages follow this structure:
- Header: version (4) + sourceDomain (4) + destDomain (4) + nonce (8) + sender (32) + recipient (32) + destCaller (32)
- Body: version (4) + burnToken (32) + mintRecipient (32) + amount (32) + messageSender (32)
Attestation
The attestation is Circle's signature over the keccak256 hash of the message bytes. It proves the message was legitimately sent on the source chain.
References
License
MIT
