I didnt have time to do a demo :( Also only base bridges are working right now, I also didn't have time to fix the CCTP after the user swaps for USDC on solana.

A seamless cross-chain bridge enabling USDC transfers between Base (Ethereum L2) and Solana using Circle's Cross-Chain Transfer Protocol (CCTP).

• Problem Being Solved
• Architecture Overview
• Tech Stack
• Setup
• Local Development
• Environment Variables
• Features

The reason I created this app is because theres always sometimes when I try to bridge something, but I get either an error, or there isn't liquidity for the token I want to bridge.

Solution!!!

We use Kyberswap and Jupiter to aggregate the best route to swap any token to USDC, and then use Circle's CCTP to bridge the USDC to Solana.

┌─────────────────────────────────────────────────────────────────┐
│                        Frontend (Next.js)                        │
│  ┌─────────────┐  ┌──────────────┐  ┌────────────────────────┐  │
│  │   Privy     │  │ CrossChain   │  │     Wallet Display     │  │
│  │   Auth      │  │   Bridge     │  │   (Base + Solana)      │  │
│  └─────────────┘  └──────────────┘  └────────────────────────┘  │
└─────────────────────────────────────────────────────────────────┘
                              │
          ┌───────────────────┼───────────────────┐
          ▼                   ▼                   ▼
┌─────────────────┐  ┌────────────────┐  ┌────────────────────┐
│   KyberSwap     │  │   Jupiter      │  │      Privy         │
│   Aggregator    │  │   Aggregator   │  │   Embedded Wallets │
│   (Base DEX)    │  │   (Solana DEX) │  │   + Gas Sponsor    │
└─────────────────┘  └────────────────┘  └────────────────────┘
          │                   │                   │
          ▼                   ▼                   ▼
┌─────────────────────────────────────────────────────────────────┐
│                    Circle CCTP Bridge                            │
│  ┌─────────────────────┐        ┌─────────────────────────────┐ │
│  │  TokenMessenger     │◄──────►│     TokenMessenger          │ │
│  │  (Base)             │  CCTP  │     (Solana)                │ │
│  └─────────────────────┘        └─────────────────────────────┘ │
└─────────────────────────────────────────────────────────────────┘

1. User inputs amount and selects token on Base
2. KyberSwap aggregates best route to swap token → USDC
3. USDC is approved for Circle's TokenMessenger contract
4. TokenMessenger burns USDC on Base, generates attestation
5. Circle attests the burn (off-chain)
6. USDC is minted to recipient on Solana

1. User inputs amount and selects token on Solana
2. Jupiter aggregates best route to swap token → USDC
3. TokenMessenger burns USDC on Solana
4. Circle attests the burn
5. USDC is minted to recipient on Base

• Node.js 18+
• Yarn or npm
• Privy account with app configured
• (Optional) KyberSwap API key
• (Optional) Jupiter API key

# Clone the repository
git clone https://github.com/yourusername/cross-chain-app.git
cd cross-chain-app

# Install dependencies
yarn install

Create a .env.local file in the root directory:

# Required: Privy Configuration
NEXT_PUBLIC_PRIVY_APP_ID=your_privy_app_id
PRIVY_APP_SECRET=your_privy_app_secret

# Optional: API Keys for better rate limits
NEXT_PUBLIC_KYBERSWAP_CLIENT_ID=cross-chain-app
NEXT_PUBLIC_JUPITER_API_KEY=your_jupiter_api_key

# Start development server
yarn dev

# Build for production
yarn build

# Start production server
yarn start

The app will be available at http://localhost:3000

• 🔐 Embedded Wallets: Users get wallets automatically on login (email, Google, Twitter)
• ⛽ Gas Sponsorship: Transactions are sponsored - users don't need native tokens for gas
• 🔄 Any Token → USDC: Swap any supported token to USDC before bridging
• 🌉 Native USDC Bridge: Uses Circle CCTP for secure, 1:1 USDC transfers
• 🎨 Premium UI: Dark mode with glassmorphism, gradients, and smooth animations
• 📱 Responsive: Works on desktop and mobile

• All bridging uses Circle's audited CCTP contracts
• Privy handles wallet security with TEE (Trusted Execution Environment)
• No wrapped or synthetic tokens - only native USDC
• Rate limiting recommended for gas sponsorship

MIT