Circle CCTP Crosschain Transfer Sample App

This sample app demonstrates how to use Circle's Cross-Chain Transfer Protocol (CCTP) to transfer USDC across chains. It walks through the full CCTP flow — approve, burn, attest, and mint — on both EVM and Solana testnets using a Next.js interface.

Note: This demo now uses injected user wallets for signing. Use testnet wallets only and do not treat this sample as production-ready custody or wallet infrastructure.

Prerequisites

• Node.js 22+
• An injected EVM wallet such as MetaMask
• An injected Solana wallet such as Phantom
• Testnet USDC on the relevant chains and native tokens for gas fees

Getting Started

1. Clone this repository:

   git clone https://github.com/circlefin/circle-cctp-crosschain-transfer.git

2. Install dependencies:

   npm install

3. Start the app in development:

   npm run dev

The app will be running at http://localhost:3000.

How It Works

• The app is built with Next.js (App Router) and uses viem for EVM interactions and @coral-xyz/anchor + @solana/web3.js for Solana interactions.
• The core transfer logic lives in a single React hook (use-cross-chain-transfer.ts) that orchestrates the four CCTP steps: approve spending, burn USDC on the source chain, retrieve attestation from Circle's IRIS API, and mint USDC on the destination chain.
• Chain configuration (contract addresses, destination domains, viem chain definitions) is centralized in a single CHAIN_CONFIGS record in chains.ts.
• The app uses the connected EVM and/or Solana wallet based on the selected source and destination chains.

Supported Chains

• Arbitrum Sepolia
• Arc Testnet
• Avalanche Fuji
• Base Sepolia
• Codex Testnet
• Edge Testnet
• Ethereum Sepolia
• HyperEVM Testnet
• Injective Testnet
• Ink Sepolia
• Linea Sepolia
• Monad Testnet
• Morph Hoodi
• Optimism Sepolia
• Pharos Atlantic
• Plume Sepolia
• Polygon Amoy
• Sei Testnet
• Solana Devnet
• Sonic Testnet
• Unichain Sepolia
• Worldchain Sepolia
• XDC Testnet

File Highlights

• src/hooks/use-cross-chain-transfer.ts: Core CCTP transfer hook (approve, burn, attest, mint)
• src/lib/chains.ts: Centralized chain configuration and contract addresses
• src/lib/solana-utils.ts: Solana-specific utilities (Anchor setup, PDA derivation, nonce decoding)
• src/app/page.tsx: Main UI for selecting chains, entering amounts, and viewing transfer progress
• src/components/timer.tsx: Transfer duration timer

Usage Notes

• This sample is scoped to testnets only.
• Connect an EVM wallet for EVM source or destination chains.
• Connect a Solana wallet for Solana source or destination chains.
• Attestation polling can take several minutes depending on source chain finality.

Scripts

• npm run dev: Start the Next.js development server
• npm run build: Build the production application
• npm run start: Start the production server
• npm run lint: Run ESLint

Security & Usage Model

This sample application:

• Assumes testnet or sandbox usage only
• Relies on injected browser wallets for signing
• Is not intended for production use without modification

See SECURITY.md for vulnerability reporting guidelines. Please report issues privately via Circle's bug bounty program.

License