BlindPay - Stablecoin to Fiat Converter

A Next.js application that enables seamless conversion between stablecoins and fiat currencies using BlindPay's API and Dynamic wallet integration.

🚀 Features

• Dynamic Wallet Integration: Connect wallets using Dynamic Labs
• BlindPay API Integration: Real-time conversion rates and execution
• KYC Verification Flow: Complete KYC verification to use BlindPay services
• User Metadata Storage: Receiver IDs stored in Dynamic user metadata
• Multi-Currency Support: Support for various stablecoins and fiat currencies
• Real-time Quotes: Get live conversion rates before executing trades

🛠 Setup

1. Install dependencies:

   bun install

2. Set up environment variables: Create a .env.local file with the following variables:

   # BlindPay API Configuration (Required)
   BLINDPAY_API_URL=https://api.blindpay.com/v1
   BLINDPAY_INSTANCE_ID=your_instance_id_here
   BLINDPAY_API_KEY=your_api_key_here
   
   # Dynamic Wallet Configuration (Required)
   NEXT_PUBLIC_DYNAMIC_ENVIRONMENT_ID=your_dynamic_environment_id_here
   
   # Contract Addresses (Optional - defaults provided)
   NEXT_PUBLIC_USDB_CONTRACT_ADDRESS=0x4D423D2cfB373862B8E12843B6175752dc75f795
   
   # BlindPay Defaults (Optional - will use sensible defaults)
   BLINDPAY_DEFAULT_NETWORK=base_sepolia
   BLINDPAY_CURRENCY_TYPE=sender
   BLINDPAY_COVER_FEES=true
   BLINDPAY_PAYMENT_METHOD=ach
   BLINDPAY_STABLECOIN_TOKEN=USDC
   BLINDPAY_FIAT_CURRENCY=USD

   To get your BlindPay credentials:

   1. Create an account on BlindPay
   2. Create a development instance
   3. Create your API key
   4. Note your instance ID and bank account ID

3. Run the development server:

   bun run dev

4. Open your browser: Navigate to http://localhost:3000

🔐 KYC Integration

How It Works

1. Wallet Connection: Users connect their wallet using Dynamic Labs
2. KYC Verification: Users complete a KYC form with personal information
3. Receiver Creation: BlindPay creates a receiver with the provided KYC data
4. Metadata Storage: The receiver ID and banking ID are stored in Dynamic user metadata using the useUserUpdateRequest hook
5. Service Access: Users can now access BlindPay services using their stored receiver ID
6. Data Persistence: All KYC data persists across sessions and devices via Dynamic's user metadata system

KYC Flow

The KYC flow includes:

• Personal information (name, email, date of birth)
• Contact details (phone number)
• Address information (street, city, state_province_region, postal code)
• Document verification (proof of address, ID documents)

Security Features

• KYC data is sent directly to BlindPay's secure API
• Receiver IDs are stored in Dynamic's encrypted user metadata
• No sensitive KYC data is stored locally
• Environment variables for development defaults

💱 How It Works

Fiat to Stablecoin (Payin)

1. Connect Wallet: Connect your wallet using Dynamic Labs
2. Complete KYC: Complete KYC verification if not already done
3. Enter Amount: Specify the USD amount to convert
4. Create Quote: Get a quote for the conversion rate
5. Get Banking Details: Receive BlindPay banking details and memo code
6. ACH Transfer: Send ACH transfer to provided banking details with memo code
7. Receive Tokens: USDC is automatically sent to your wallet after payment confirmation

Stablecoin to Fiat (Payout)

1. Connect Wallet: Connect your wallet using Dynamic Labs
2. Complete KYC: Complete KYC verification if not already done
3. Enter Amount: Specify the stablecoin amount to convert
4. Create Quote: Get a quote for the conversion
5. Approve Tokens: Approve BlindPay contract to spend your tokens
6. Execute Payout: BlindPay processes the payout to your bank account

🏗 Architecture

Frontend Components

• KYCFlow: Handles KYC verification and receiver creation
• ConversionCard: UI for currency conversion inputs
• WalletInfo: Displays wallet balances and connection status
• TransactionHistory: Shows conversion history

Backend API Routes

• /api/receivers: Manages BlindPay receiver creation and TOS acceptance
• /api/payin: Handles fiat-to-stablecoin conversions
• /api/convert: Manages stablecoin-to-fiat conversions
• /api/banking-details: Provides banking information for payins

Key Integrations

• Dynamic Labs: Wallet connection and user metadata management
• BlindPay API: Conversion quotes, execution, and banking details
• Wagmi/Viem: Blockchain interactions and token approvals

🔧 Development

Adding New Currencies

1. Update config.currencies in src/lib/config.ts
2. Add token mapping in config.tokenMapping
3. Update conversion logic in API routes

Customizing KYC Flow

1. Modify the KYCFlow component in src/components/KYCFlow.tsx
2. Update the receivers API route for additional KYC fields
3. Add validation and error handling as needed

Environment Variables

All configuration is done through environment variables to ensure:

• No hardcoded values in production
• Easy configuration management
• Secure credential handling

🚨 Important Notes

• KYC Required: Users must complete KYC verification before using BlindPay services
• Receiver ID Storage: Receiver IDs are automatically stored in Dynamic user metadata
• No Local Storage: Sensitive KYC data is not stored locally
• Development Mode: Uses placeholder KYC data for development (configure via env vars)

📚 Resources

• BlindPay API Documentation
• Dynamic Labs Documentation
• Wagmi Documentation
• Viem Documentation