Blockchain Integration API Documentation

Based on OpenAPI specification: chain.yaml

📋 Executive Summary

Audience: Stakeholders

The Blockchain Integration service provides comprehensive connectivity to multiple blockchain networks, enabling secure smart contract deployment, cross-chain asset transfers, and decentralized finance (DeFi) protocol integration. This service ensures seamless interoperability between traditional financial operations and blockchain-based assets, supporting multi-chain strategies and advanced DeFi yield optimization while maintaining institutional-grade security and compliance standards.

🎯 Service Overview

Audience: All

Business Purpose

• Multi-blockchain connectivity for diverse asset support and liquidity access
• Smart contract deployment and management for automated financial operations
• Cross-chain bridge operations for seamless asset transfers between networks
• DeFi protocol integration for yield optimization and liquidity provision
• Real-time blockchain monitoring and transaction status tracking

Technical Architecture

• Multi-chain RPC node management with automatic failover capabilities
• Smart contract factory patterns for standardized deployments
• Cross-chain bridge integration with atomic swap capabilities
• Event-driven blockchain monitoring with real-time notifications
• Hardware security module (HSM) integration for private key management

📊 API Specifications

Audience: Technical

Base Configuration

servers:

• url: https://api.quub.fi/v1/chain description: Production environment
• url: https://sandbox-api.quub.fi/v1/chain description: Sandbox environment

security:

• BearerAuth: []

Authentication & Authorization (Chain Service)

• JWT token with chain:read and chain:write scopes required
• Organization-scoped access with orgId validation for wallet operations
• Role-based permissions for smart contract deployment & management
• Hardware wallet integration for high-value transaction signing

🚀 Core Endpoints

Audience: Technical + Project Teams

Network Management

Get Supported Networks

Business Use Case: Retrieve list of supported blockchain networks and their status

Response Example:

{
  "networks": ["ethereum", "polygon", "arbitrum"],
  "status": "available"
}

Get Network Status

Business Use Case: Monitor blockchain network health/performance

Response Example:

{
  "chainId": "ethereum",
  "blockHeight": 20719232,
  "gasPrice": "21 gwei"
}

Wallet Operations

Create Wallet

Business Use Case: Generate new blockchain wallets for custody & transaction management

Request Example:

{
  "accountId": "user-123"
}

Response Example:

{
  "walletId": "wal_01",
  "address": "0xabc...def"
}

Project Implementation Notes

• implement secure key generation (HSM / secure enclave)
• store addresses only, never private keys
• validate signer permissions
• support wallet recovery & backup strategy

Get Wallet Balance

Business Use Case: Monitor wallet asset balances across tokens/networks

Response Example:

{
  "address": "0xabc...def",
  "balances": [
    { "symbol": "ETH", "amount": "1.234" },
    { "symbol": "USDC", "amount": "200.00" }
  ]
}

Transaction Management

Send Transaction

Business Use Case: Execute blockchain transactions

Request Example:

{
  "to": "0x111...222",
  "value": "0.05",
  "asset": "ETH"
}

Response Example:

{
  "txHash": "0x9f...b1",
  "status": "PENDING"
}

Get Transaction Status

Business Use Case: Track transaction confirmations

Smart Contract Operations

Deploy Contract

Business Use Case: Deploy smart contracts for exchange, escrow, DeFi ops

Call Contract Function

Business Use Case: Interact with deployed smart contracts

DeFi Integration

Get DeFi Protocols

Business Use Case: discover yield sources / liquidity protocols

Execute DeFi Operation

Business Use Case: execute yield operations or liquidity management

🔐 Security Implementation

Audience: Technical + Project Teams

Multi-tenant Isolation

Private Key Management

• HSM-backed key generation & storage
• multi-sig wallet support (configurable thresholds)
• BIP32/BIP44 deterministic key derivation
• secure encrypted backup & recovery

Transaction Security

📈 Business Workflows

Audience: Stakeholders + Project Teams

Primary Workflow: Cross-Chain Asset Transfer

Value: liquidity mobility across networks Success Metrics: <5 min transfer completion, 99.99% success rate

Secondary Workflow: DeFi Yield Optimization

Value: maximize idle asset yield Success Metrics: >5% annual improvement, automated rebalancing

🧪 Integration Guide

Audience: Project Teams

• Development Setup
• Code Examples (JS/Python)
• Testing Strategy

📊 Error Handling

Audience: Technical + Project Teams

📋 Implementation Checklist

Audience: Project Teams

Pre-Development

• blockchain RPC endpoints configured
• HSM / secure key management in place
• multi-sig requirements defined
• DeFi integration requirements documented
• security audit procedure agreed

Development Phase

• multi-network wallet mgmt
• tx signing & broadcasting
• smart contract deployment + interaction
• DeFi protocol integration
• event monitoring & tx status tracking
• gas price estimation strategy

Testing Phase

• unit tests (blockchain ops)
• integration tests (testnet)
• secure key mgmt tests
• performance tests
• cross-chain bridge tests
• DeFi interaction tests

Production Readiness

• prod node endpoints configured
• HSM fully validated
• multi-sig procedures tested
• monitoring + alerts configured
• incident response documented
• wallet backup + recovery validated

📈 Monitoring & Observability

Key Metrics

• tx success rate (>99.5%)
• avg confirmation time per network
• gas optimization efficiency
• DeFi yield performance
• cross-chain bridge success rate

🔄 API Versioning & Evolution

Current Version: v1

• Multi-chain: Ethereum, Polygon, Arbitrum
• Smart contract ops
• DeFi integration
• cross-chain transfers

Planned Enhancements (v1.1)

• Solana, Avalanche
• advanced DeFi strategies
• NFT marketplace support
• L2 scaling optimization

Breaking Changes (v2.0 - Future)

• advanced multi-sig policy engine
• account abstraction (gasless tx)
• zero-knowledge privacy
• institutional custody integrations

Last updated: November 2, 2025 • API Version: v1 • Document Version: 1.0