📋 StellarPOS Smart Contracts

Comprehensive Soroban smart contracts for StellarPOS payment processing, business logic, and financial operations on the Stellar blockchain.

Overview

StellarPOS Smart Contracts provide a complete suite of blockchain-based business logic for point-of-sale operations, including payment processing, escrow services, loyalty programs, and financial management.

Contracts Overview

Payment Processor Contract

Core payment processing contract handling:

• Multi-Asset Payments: XLM and custom token support
• Atomic Transactions: Guaranteed payment execution
• Fee Management: Configurable transaction fees
• Payment Verification: Cryptographic proof of payment
• Refund Processing: Automated refund mechanisms

Escrow Service Contract

Secure escrow services for complex transactions:

• Multi-Party Escrow: Support for multiple parties
• Time-locked Releases: Automated time-based releases
• Dispute Resolution: Built-in arbitration system
• Partial Releases: Milestone-based payments
• Emergency Recovery: Admin recovery mechanisms

Loyalty Program Contract

Customer loyalty and rewards management:

• Point Accumulation: Earn points on purchases
• Tier Management: Customer loyalty tiers
• Reward Redemption: Points-to-value conversion
• Expiration Handling: Automatic point expiration
• Bonus Campaigns: Time-limited promotions

Treasury Management Contract

Business treasury and financial operations:

• Multi-signature Wallets: Secure fund management
• Automated Distributions: Revenue sharing
• Reserve Management: Maintain operating reserves
• Yield Generation: Stake rewards integration
• Financial Reporting: On-chain audit trails

Merchant Registry Contract

Merchant onboarding and management:

• Merchant Registration: Decentralized merchant onboarding
• KYC Integration: Identity verification hooks
• Fee Structure Management: Per-merchant fee tiers
• Status Management: Active/inactive merchant states
• Compliance Tracking: Regulatory compliance monitoring

Technology Stack

• Smart Contract Platform: Soroban (Stellar)
• Programming Language: Rust
• Development Framework: Soroban CLI
• Testing Framework: Soroban Test Framework
• Documentation: Cargo Doc
• Deployment: Stellar Testnet & Mainnet
• Monitoring: Stellar Expert integration

Project Structure

contracts/
├── payment-processor/   # Core payment processing
│   ├── src/
│   │   ├── lib.rs      # Main contract logic
│   │   ├── types.rs    # Data structures
│   │   ├── storage.rs  # Storage management
│   │   ├── events.rs   # Event definitions
│   │   └── utils.rs    # Utility functions
│   ├── Cargo.toml
│   └── README.md
├── escrow-service/      # Escrow and dispute resolution
│   ├── src/
│   │   ├── lib.rs
│   │   ├── escrow.rs   # Escrow logic
│   │   ├── dispute.rs  # Dispute resolution
│   │   └── timelock.rs # Time-based releases
│   ├── Cargo.toml
│   └── README.md
├── loyalty-program/     # Customer loyalty system
│   ├── src/
│   │   ├── lib.rs
│   │   ├── points.rs   # Points management
│   │   ├── tiers.rs    # Tier system
│   │   └── rewards.rs  # Reward redemption
│   ├── Cargo.toml
│   └── README.md
├── treasury/           # Treasury management
│   ├── src/
│   │   ├── lib.rs
│   │   ├── multisig.rs # Multi-signature logic
│   │   ├── treasury.rs # Treasury operations
│   │   └── yield.rs    # Yield generation
│   ├── Cargo.toml
│   └── README.md
├── merchant-registry/  # Merchant management
│   ├── src/
│   │   ├── lib.rs
│   │   ├── registry.rs # Merchant registration
│   │   ├── kyc.rs      # KYC integration
│   │   └── fees.rs     # Fee management
│   ├── Cargo.toml
│   └── README.md
├── shared/             # Shared libraries
│   ├── src/
│   │   ├── lib.rs
│   │   ├── types.rs    # Common types
│   │   ├── utils.rs    # Shared utilities
│   │   └── errors.rs   # Error definitions
│   ├── Cargo.toml
│   └── README.md
├── scripts/            # Deployment and utility scripts
├── tests/              # Integration tests
└── docs/               # Documentation

Prerequisites

• Rust 1.70+
• Soroban CLI
• Stellar CLI
• Git

Installation

# Clone the repository
git clone https://github.com/StellarPOS-App/contracts.git
cd contracts

# Install Soroban CLI (if not installed)
cargo install --locked soroban-cli

# Build all contracts
make build

# Run tests
make test

# Deploy to testnet
make deploy-testnet

Environment Setup

# Setup Stellar testnet
soroban config network add testnet \
  --rpc-url https://soroban-testnet.stellar.org:443 \
  --network-passphrase "Test SDF Network ; September 2015"

# Generate test identity
soroban config identity generate alice
soroban config identity address alice

# Fund test account
soroban config identity fund alice --network testnet

📋 Contract Functions

Payment Processor

// Initialize payment processor
pub fn initialize(env: Env, admin: Address, fee_rate: u32) -> Result<(), Error>

// Process payment
pub fn process_payment(
    env: Env,
    payer: Address,
    merchant: Address,
    amount: i128,
    asset: Address,
    memo: String
) -> Result<u64, Error>

// Verify payment
pub fn verify_payment(env: Env, payment_id: u64) -> Result<PaymentStatus, Error>

// Process refund
pub fn process_refund(
    env: Env,
    payment_id: u64,
    refund_amount: i128,
    reason: String
) -> Result<u64, Error>

Escrow Service

// Create escrow
pub fn create_escrow(
    env: Env,
    buyer: Address,
    seller: Address,
    amount: i128,
    asset: Address,
    terms: EscrowTerms
) -> Result<u64, Error>

// Release funds
pub fn release_funds(env: Env, escrow_id: u64) -> Result<(), Error>

// Raise dispute
pub fn raise_dispute(
    env: Env,
    escrow_id: u64,
    reason: String
) -> Result<(), Error>

// Resolve dispute
pub fn resolve_dispute(
    env: Env,
    escrow_id: u64,
    resolution: DisputeResolution
) -> Result<(), Error>

Loyalty Program

// Register customer
pub fn register_customer(env: Env, customer: Address) -> Result<(), Error>

// Award points
pub fn award_points(
    env: Env,
    customer: Address,
    points: u64,
    transaction_id: String
) -> Result<(), Error>

// Redeem points
pub fn redeem_points(
    env: Env,
    customer: Address,
    points: u64
) -> Result<i128, Error>

// Get customer tier
pub fn get_customer_tier(env: Env, customer: Address) -> Result<CustomerTier, Error>

🧪 Testing

# Run all tests
make test

# Run specific contract tests
cargo test -p payment-processor

# Run integration tests
cargo test --test integration

# Test with coverage
cargo tarpaulin --out Html

# Benchmark tests
cargo bench

Deployment

Testnet Deployment

# Deploy all contracts to testnet
make deploy-testnet

# Deploy specific contract
soroban contract deploy \
  --wasm target/wasm32-unknown-unknown/release/payment_processor.wasm \
  --network testnet \
  --source alice

Mainnet Deployment

# Build optimized contracts
make build-release

# Deploy to mainnet
make deploy-mainnet

# Verify deployment
soroban contract invoke \
  --id CONTRACT_ID \
  --network mainnet \
  --source alice \
  -- get_version

Security Features

Access Control

• Role-based Permissions: Admin, merchant, customer roles
• Multi-signature Support: Secure admin operations
• Time-lock Mechanisms: Delayed sensitive operations
• Emergency Pause: Circuit breaker functionality

Financial Security

• Overflow Protection: Safe arithmetic operations
• Reentrancy Guards: Prevent reentrancy attacks
• Input Validation: Comprehensive parameter checking
• Rate Limiting: Transaction frequency controls

Audit Trail

• Event Logging: Comprehensive event emission
• State Tracking: Complete state change history
• Transaction Receipts: Cryptographic proofs
• Compliance Reporting: Regulatory compliance data

📊 Contract Interactions

graph TB
    A[Frontend] --> B[Backend API]
    B --> C[Payment Processor]
    B --> D[Escrow Service]
    B --> E[Loyalty Program]
    C --> F[Treasury]
    D --> F
    E --> F
    G[Merchant Registry] --> C
    G --> D
    H[Stellar Network] --> C
    H --> D
    H --> E
    H --> F

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📚 Documentation

• Contract Architecture
• API Reference
• Integration Guide
• Security Guidelines
• Deployment Guide
• Troubleshooting

🤝 Contributing

We welcome contributions from blockchain developers worldwide! 🌍⛓️

Quick Start

1. ⭐ Star this repository if you find it helpful
2. 🍴 Fork the repository to your GitHub account
3. 📥 Clone your fork locally
4. 🌿 Create a feature branch (git checkout -b feature/amazing-feature)
5. ✨ Make your changes and add tests
6. ✅ Commit your changes (git commit -m 'Add some amazing feature')
7. 📤 Push to your branch (git push origin feature/amazing-feature)
8. 🔄 Open a Pull Request

👥 Our Contributors

We have an amazing community of 10+ active blockchain contributors! See our Contributors Guide for the full list.

🎯 Ways to Contribute

• 🐛 Report contract bugs and vulnerabilities
• 💡 Suggest improvements to smart contract logic
• 📝 Improve documentation and code comments
• 🧪 Write comprehensive tests and security audits
• 🔒 Enhance security features and access controls
• ⚡ Optimize gas usage and contract efficiency
• 🔍 Add monitoring and analytics features
• 🛠️ Improve deployment scripts and tooling

📋 Good First Issues

New to Soroban development? Check out our Good First Issues!

Detailed Contributing Guide: CONTRIBUTING.md

📄 License

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

🔗 Links

• Frontend Repository
• Backend Repository
• Soroban Documentation
• Stellar Developer Portal