VeloPay - Blockchain Payment System

VeloPay is a fully-fledged blockchain-based payment system built on Substrate, enabling secure digital payments with fiat on/off ramp capabilities through mint and burn operations.

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🚀 Features

💸 Core Payment Features

• Peer-to-Peer Transfers: Send and receive VCS instantly
• Transaction History: Complete audit trail of all transactions
• Multi-signature Support: Enhanced security for high-value transactions

🏦 Fiat On/Off Ramp

• Mint Operations: Convert fiat to VCS through verified bank transfers
• Burn Operations: Convert VCS back to fiat currency
• Compliance Framework: Built-in KYC/AML verification system

🔐 Security & Compliance

• KYC Verification: Identity verification for regulatory compliance
• Admin Controls: Centralized oversight for mint/burn approvals
• JWT Authentication: Secure API access with coin-based auth
• Rate Limiting: DDoS protection and abuse prevention

🎯 Technical Highlights

• Substrate Framework: Built on Polkadot's battle-tested blockchain framework
• RESTful API: Comprehensive HTTP API for easy integration
• PostgreSQL Database: Robust data persistence layer
• Real-time Updates: WebSocket support for live transaction monitoring

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📁 Project Structure

velopay/
├── velo-chain/              # Substrate blockchain node
│   ├── pallets/
│   │   └── velopay/         # VeloPay pallet (core logic)
│   ├── runtime/             # Chain runtime configuration
│   └── node/                # Node implementation
│
├── velopay-api/             # REST API Gateway (Actix-web + Rust)
│   ├── src/
│   │   ├── chain/           # Blockchain client integration
│   │   ├── db/              # Database repositories
│   │   ├── middleware/      # Auth & admin middleware
│   │   ├── models/          # Data models
│   │   ├── routes/          # API endpoints
│   │   └── services/        # Business logic
│   └── migrations/          # Database migrations
│
└── velopay-web/             # Frontend (SvelteKit)
    ├── src/
    │   ├── lib/             # Shared components & utilities
    │   └── routes/          # Application pages
    └── static/              # Static assets

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🛠️ Technology Stack

Blockchain (velo-chain)

• Framework: Substrate 4.0
• Language: Rust
• Consensus: Aura (Block Production) + GRANDPA (Finality)
• Runtime: Custom VeloPay pallet with mint/burn logic

API Gateway (velopay-api)

• Framework: Actix-web 4.x
• Language: Rust
• Database: PostgreSQL 16
• Authentication: JWT (jsonwebcoin)
• Rate Limiting: Governor middleware
• Client: Subxt for blockchain interaction

Frontend (velopay-web)

• Framework: SvelteKit
• Language: TypeScript
• Styling: TailwindCSS
• Build Tool: Vite
• State Management: Svelte stores

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📋 Prerequisites

System Requirements

• Operating System: Windows 10/11, Linux, or macOS
• RAM: Minimum 8GB (16GB recommended)
• Disk Space: 20GB+ for blockchain data

Software Dependencies

• Rust: 1.70 or higher
• Node.js: 18.x or higher
• PostgreSQL: 14.x or higher
• Git: Latest version

Development Tools

• Cargo: Rust package manager (comes with Rust)
• npm/pnpm: Node package manager
• psql: PostgreSQL client

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🚀 Quick Start

1. Clone Repository

git clone https://github.com/ChronoCoders/velopay.git
cd velopay

2. Start Blockchain Node

cd velo-chain

# Build the node (first time only)
cargo build --release

# Start Alice node (development)
./target/release/velo-chain --dev --tmp

Alternative: Use provided batch scripts:

# Windows
start-local.bat

# Linux/Mac
./start-local.sh

3. Setup Database

# Create database
psql -U postgres
CREATE DATABASE velopay_db;
CREATE USER velopay_user WITH PASSWORD 'your_password';
GRANT ALL PRIVILEGES ON DATABASE velopay_db TO velopay_user;
\q

# Run migrations
cd velopay-api
sqlx migrate run

4. Configure API

Create .env file in velopay-api/:

# Database
DATABASE_URL=postgresql://velopay_user:your_password@localhost:5432/velopay_db

# Server
HOST=127.0.0.1
PORT=8080

# JWT
JWT_SECRET=your-super-secret-jwt-key-min-48-chars
JWT_EXPIRATION=86400

# Admin
ADMIN_API_KEY=your-admin-api-key
ADMIN_SEED=//Alice

# Chain
CHAIN_ENDPOINT=ws://127.0.0.1:9944

# CORS
CORS_ALLOWED_ORIGINS=http://localhost:5173,http://localhost:3000

5. Start API Server

cd velopay-api
cargo run --release

API will be available at: http://localhost:8080

6. Start Frontend

cd velopay-web
npm install
npm run dev

Frontend will be available at: http://localhost:5173

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📚 API Documentation

Authentication Endpoints

Register User

POST /api/v1/auth/register
Content-Type: application/json

{
  "email": "user@example.com",
  "password": "SecurePass123!",
  "wallet_address": "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY"
}

Login

POST /api/v1/auth/login
Content-Type: application/json

{
  "email": "user@example.com",
  "password": "SecurePass123!"
}

Payment Endpoints

Send Payment

POST /api/v1/payments
Authorization: Bearer <JWT_TOKEN>
Content-Type: application/json

{
  "from_address": "5GrwvaEF...",
  "to_address": "5FHneW46...",
  "amount": "100.50"
}

Get Transaction History

GET /api/v1/payments/history/{wallet_address}?limit=10&offset=0
Authorization: Bearer <JWT_TOKEN>

Mint/Burn Operations

Create Mint Request

POST /api/v1/mint
Authorization: Bearer <JWT_TOKEN>
Content-Type: application/json

{
  "wallet_address": "5GrwvaEF...",
  "amount": "1000.00",
  "bank_reference": "BANK-REF-12345"
}

Create Burn Request

POST /api/v1/burn
Authorization: Bearer <JWT_TOKEN>
Content-Type: application/json

{
  "wallet_address": "5GrwvaEF...",
  "amount": "500.00",
  "bank_account": "TR330006100519786457841326"
}

KYC Endpoints

Submit KYC

POST /api/v1/kyc
Authorization: Bearer <JWT_TOKEN>
Content-Type: application/json

{
  "document_hash": "0xabcdef1234567890",
  "full_name": "John Doe",
  "date_of_birth": "1990-01-01",
  "country": "US",
  "wallet_address": "5GrwvaEF..."
}

Admin Endpoints

Get Pending Mint Requests

GET /admin/v1/mint/pending
X-Admin-API-Key: <ADMIN_API_KEY>

Approve Mint Request

POST /admin/v1/mint/{request_id}/approve
X-Admin-API-Key: <ADMIN_API_KEY>
Content-Type: application/json

{
  "admin_id": "uuid-here",
  "chain_request_id": 0
}

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🧪 Testing

Run API Tests

cd velopay-api

# Run test suite
test-api.bat

# Or manually test endpoints
curl http://localhost:8080/health

Run Chain Tests

cd velo-chain
cargo test --release

Run Frontend Tests

cd velopay-web
npm run test

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🏗️ Architecture

System Flow

User → Frontend (SvelteKit) → API Gateway (Actix) → PostgreSQL
                                    ↓
                              Blockchain Node (Substrate)

Key Components

1. VeloPay Pallet: Core blockchain logic for coin operations
2. API Gateway: RESTful interface for user interactions
3. Database: Off-chain data persistence for fast queries
4. Frontend: User-friendly web interface

Security Model

• JWT Authentication: Secure API access
• Admin API Keys: Privileged operations require admin key
• Rate Limiting: Protection against abuse
• KYC/AML: Regulatory compliance built-in

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🔧 Configuration

Chain Configuration

Edit velo-chain/node/src/chain_spec.rs:

• Genesis accounts
• Initial balances
• Validator set

API Configuration

All configuration via .env file:

• Database connection
• JWT settings
• CORS policies
• Rate limits

Frontend Configuration

Edit velopay-web/svelte.config.js:

• API endpoint URLs
• Build settings
• Adapters

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🚢 Deployment

Production Considerations

1. Use Strong Secrets: Generate secure keys for production
2. Enable HTTPS: Use SSL certificates for API and frontend
3. Database Backups: Regular PostgreSQL backups
4. Monitoring: Set up logging and alerts
5. Rate Limiting: Adjust based on expected load

Docker Deployment (Coming Soon)

docker-compose up -d

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🤝 Contributing

We welcome contributions! Please follow these steps:

1. Fork the repository
2. Create feature branch (git checkout -b feature/AmazingFeature)
3. Commit changes (git commit -m 'Add AmazingFeature')
4. Push to branch (git push origin feature/AmazingFeature)
5. Open Pull Request

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📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

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🙏 Acknowledgments

• Substrate/Polkadot: For the amazing blockchain framework
• Actix-web: For the performant Rust web framework
• SvelteKit: For the elegant frontend framework

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📞 Support

• Issues: GitHub Issues
• Email: support@velopay.com
• Telegram: @velopay_community

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🗺️ Roadmap

• Core blockchain functionality
• REST API implementation
• Database integration
• Authentication system
• Admin panel endpoints
• Frontend UI completion
• Mobile application
• Multi-chain support
• Staking mechanism
• Governance module

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Built with ❤️ by ChronoCoders Team