Technical Architecture

SafeBank's architecture is designed for full autonomy, privacy, and scalability — combining DeFi primitives with real-world banking infrastructure.

System Overview

+-------------------------------------------------------------+
|                  SafeBank Application Layer                 |
|  (Mobile / Web App – React Native + Next.js + GraphQL)      |
+-------------------------------------------------------------+
|  SafeBank API  |  IDSentric KYC  |  CredZK ZKP Prover       |
+-------------------------------------------------------------+
|  Smart Contracts:                                            |
|  - $SBANK Token (ERC-20)                                    |
|  - Smart Accounts (ERC-6551)                                |
|  - Lending & Bill Buffer Contracts                           |
|  - DAO Governance                                            |
+-------------------------------------------------------------+
|  Networks: Ethereum • Polygon • Base • Arbitrum             |
|  Payments: Worldpay • NFC ATM Bridge • ACH/Wire Rails       |
+-------------------------------------------------------------+

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Core Components

1. Application Layer

Mobile Applications

• React Native for iOS and Android
• NFC integration for Tap-to-Pay
• Biometric authentication
• Real-time transaction updates

Web Dashboard

• Next.js for merchant portal
• Real-time analytics
• Transaction management
• Reporting and exports

API Layer

• GraphQL for flexible queries
• REST endpoints for integrations
• WebSocket for real-time updates
• Rate limiting and security

2. Identity & Compliance Layer

IDSentric Integration

• KYC/KYB verification
• Document validation
• Liveness detection
• Continuous monitoring

On-Chain Identity

• Verifiable credentials
• Privacy-preserving attestations
• Portable identity across protocols
• Compliance oracle integration

3. ZKP Lending System

CredZK Prover Module

The zero-knowledge proof system operates in three phases:

Phase 1: Local Document Processing

User Device -> Document Upload -> Local Verification -> ZK Proof Generation

• Financial documents processed locally on user's device
• Sensitive data never leaves user control
• Cryptographic proofs generated using CredZK SDK

Phase 2: Proof Submission

ZK Proof -> SafeBank Lending Contract -> On-Chain Validation

• Only proofs submitted to blockchain
• Smart contract validates cryptographic attestations
• No raw data stored or transmitted

Phase 3: Credit Decision

Validated Proof -> Credit Scoring Algorithm -> Loan Approval -> USDC Release

• Automated underwriting based on verified proofs
• Dynamic credit limits
• Instant approval and fund disbursement

Technical Implementation

contract SafeBankLending {
    // Verify ZK proof and issue credit
    function requestLoan(
        bytes calldata zkProof,
        uint256 amount,
        uint256 term
    ) external returns (uint256 loanId) {
        // Verify proof validity
        require(verifyZKProof(zkProof), "Invalid proof");
        
        // Calculate credit score from proof
        uint256 creditScore = calculateScore(zkProof);
        require(creditScore >= MIN_SCORE, "Insufficient credit");
        
        // Issue loan
        loanId = _issueLoan(msg.sender, amount, term);
        emit LoanIssued(msg.sender, loanId, amount);
    }
}

4. Smart Account System (ERC-6551)

Every user gets a token-bound account that functions as both:

• Cryptocurrency wallet
• Traditional bank account (routing + account number)

Features:

• Multi-signature support
• Social recovery
• Programmable spending limits
• Automated yield strategies
• Bill Buffer management

5. Bill Buffer Contract

AI-Powered Liquidity Management

Income -> Bill Buffer Analysis -> Reserve Calculation -> Excess -> DeFi Yield

Smart Contract Logic:

contract BillBuffer {
    struct UserBuffer {
        uint256 reserveAmount;      // 90-day expense buffer
        uint256 yieldBalance;       // Excess in yield strategies
        uint256 lastUpdateTime;
        Strategy[] activeStrategies;
    }
    
    // AI updates reserve requirements
    function updateBuffer(address user, uint256 newReserve) 
        external onlyAIOracle {
        // Rebalance between reserve and yield
    }
}

Integrated DeFi Protocols:

• Aave (lending)
• Compound (lending)
• Uniswap (liquidity provision)
• Convex (yield optimization)

6. Payment Infrastructure

Worldpay Integration

Customer Tap -> NFC Reader -> Worldpay Gateway -> SafeBank API -> 
Blockchain Settlement -> Merchant Account

ISO-8583 ATM Bridge

ATM Request -> ISO-8583 Message -> SafeBank Validator -> 
On-Chain Balance Check -> Approval -> Cash Dispensed

Settlement Flow:

• Instant confirmation for small amounts (under $100)
• Batched settlement for cost optimization
• Real-time merchant notifications
• Automatic reconciliation

7. Autonomous Banking Layer

AI Liquidity Manager

# Predictive model for cash flow
def predict_liquidity_needs(user_history):
    # ML model predicts next 90 days
    expenses = forecast_expenses(user_history)
    income = forecast_income(user_history)
    
    # Calculate optimal buffer
    buffer = calculate_safe_buffer(expenses, income)
    
    # Update on-chain
    update_buffer_contract(user, buffer)

Smart Credit Underwriter

ZK Proof -> Feature Extraction -> ML Credit Model -> 
Risk Assessment -> Dynamic Limit Calculation

Compliance Oracle

Transaction -> AML Check -> Sanctions Screen -> 
Risk Score -> Allow/Block/Review Decision

---

Network Architecture

Multi-Chain Deployment

Network	Purpose	Features
Ethereum	Main governance & token	High security, established DeFi
Polygon	Consumer transactions	Low fees, fast finality
Base	Merchant settlements	Coinbase ecosystem, fiat ramps
Arbitrum	DeFi integrations	Low cost, Ethereum security

Cross-Chain Bridge

Source Chain -> Lock Assets -> Mint Wrapped -> Destination Chain
Destination Chain -> Burn Wrapped -> Unlock Assets -> Source Chain

Security:

• Multi-signature validation
• Time-locks for large transfers
• Fraud proofs
• Insurance fund

---

Data Architecture

On-Chain Data

• Account balances
• Transaction history
• ZK proofs (not raw documents)
• Governance votes
• Smart account configurations

Off-Chain Data (Encrypted)

• User profile metadata
• Transaction descriptions
• Merchant details
• Analytics aggregates

Privacy Architecture

User Data -> Local Encryption -> ZK Proof Generation -> 
On-Chain Proof -> Verification -> No Raw Data Storage

Key Principles:

• Zero-knowledge by default
• Minimal data collection
• User-controlled sharing
• Encrypted at rest and in transit
• Regular data purging

---

Scalability Solutions

Layer 2 Scaling

• Optimistic rollups for high-throughput transactions
• ZK-rollups for privacy-sensitive operations
• State channels for instant micropayments

Sharding Strategy

• User sharding by account ID
• Transaction sharding by type
• Geographic sharding for compliance

Caching & Performance

• Redis for hot data
• IPFS for document storage (encrypted)
• CDN for static assets
• GraphQL for efficient queries

---

Security Architecture

Defense in Depth:

1. Application Layer

   • Input validation
   • Rate limiting
   • CORS policies
   • SSL/TLS encryption

2. API Layer

   • JWT authentication
   • API key rotation
   • Request signing
   • Anomaly detection

3. Smart Contract Layer

   • Formal verification
   • Multi-sig admin
   • Timelock upgrades
   • Circuit breakers

4. Infrastructure Layer

   • DDoS protection
   • WAF (Web Application Firewall)
   • Intrusion detection
   • Regular penetration testing

Learn more about security

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Development Stack

Frontend:

• React Native (Mobile)
• Next.js (Web)
• TypeScript
• TailwindCSS

Backend:

• Node.js
• GraphQL
• PostgreSQL
• Redis

Blockchain:

• Solidity
• Hardhat
• OpenZeppelin
• Chainlink (Oracles)

AI/ML:

• Python
• TensorFlow
• scikit-learn
• Pandas

Infrastructure:

• AWS / GCP
• Kubernetes
• Docker
• GitHub Actions

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Monitoring & Observability

Metrics:

• Transaction throughput
• Gas costs
• API latency
• Error rates
• User engagement

Alerting:

• Real-time anomaly detection
• Security incident response
• System health monitoring
• Business metrics tracking

Compliance Reporting:

• AML transaction monitoring
• Regulatory reporting
• Audit trails
• Privacy compliance (GDPR, CCPA)

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Future Enhancements

Phase 2 (2026-2027):

• AI-powered personal financial advisor
• Cross-border remittances
• Institutional lending pools
• DeFi protocol integrations

Phase 3 (2027-2028):

• Fully autonomous credit decisions
• Predictive cash flow management
• Global ATM network expansion
• Central bank digital currency (CBDC) support

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