Web3 Engineer

Wonnpay FZE; Dubai; On-site; AED 300,000 - 460,000; Full time

Job summary

Wonnpay FZE in Dubai is seeking a senior blockchain engineer to design, develop, and maintain blockchain and Web3 services powering the WonnPay platform. You will work on on- and off-ramp integrations and multi-network support.

You will implement secure APIs, custody wallet integrations (Fireblocks), and robust transaction monitoring, while collaborating with Backend, Frontend, Product, QA, and Compliance teams.

Qualifications

• 5+ years of professional software engineering with blockchain/Web3 focus.
• Hands-on with EVM-compatible networks and blockchain transaction processing.
• Experience with Fireblocks or MPC custody platforms is preferred.
• Experience with Solana/SPL tokens.
• Experience integrating crypto on-ramps/off-ramps.

Responsibilities

• Design, develop, and maintain blockchain/Web3 services for the WonnPay platform.
• Integrate on/off ramp solutions and Virtual IBAN setup as applicable.
• Maintain multi-network integrations (Ethereum, Polygon, Tron/TRC-20, Solana).
• Build and secure crypto deposit/withdrawal flows, wallets, and monitoring.
• Collaborate with Backend, Frontend, Product, QA, Compliance, and Operations teams.

Skills

Blockchain/Web3

Node.js/TypeScript

Solidity

Fireblocks/MPC custody

Stablecoins USDT/USDC

EVM networks

On/off ramp integration

Security/key management

REST APIs/backend

Payments/Fintech

Tools

TRON/TRC-20

AWS/cloud-native

Job description

Key Responsibilities

• Design, develop, and maintain blockchain and Web3 services supporting the WonnPay platform.
• On and off ramp integration and VIBAN
• Integrate and maintain blockchain networks such as Ethereum, Polygon, Tron/TRC-20, Solana, and other supported networks.
• Build and maintain crypto deposit and withdrawal flows, including address generation, transaction monitoring, confirmations, fee handling, and reconciliation.
• Work with Fireblocks and other blockchain infrastructure providers for wallet and transaction management.
• Develop secure APIs and backend services for blockchain-related functionality.
• Implement blockchain transaction monitoring, retry mechanisms, failure handling, and reconciliation processes.
• Work with stablecoins such as USDT and USDC across multiple networks.
• Support integration of additional digital assets and networks as the product expands.
• Work closely with Backend, Frontend, Product, QA, Compliance, and Operations teams to deliver production-ready Web3 features.
• Investigate and resolve blockchain transaction issues, including stuck, failed, delayed, or incorrectly routed transactions.
• Monitor blockchain infrastructure and proactively identify reliability, performance, and security issues.
• Implement appropriate security controls around private keys, signing processes, wallet operations, and transaction authorization.
• Participate in architecture discussions, technical design, code reviews, testing, and production releases.
• Prepare technical documentation for blockchain integrations and operational procedures.
• Support incident investigation and root-cause analysis for blockchain-related production issues.

Required Skills & Experience

• 5+ years of professional software engineering experience, with strong hands-on experience in blockchain/Web3.
• Strong understanding of blockchain fundamentals, wallets, addresses, transactions, gas/fees, confirmations, and network mechanics.
• Hands-on experience with EVM-compatible networks and blockchain transaction processing.
• Strong experience with TRON/TRC-20 is highly desirable.
• Experience working with USDT, USDC, and other stablecoins across multiple blockchain networks.
• Hands-on experience integrating crypto on-ramp and off-ramp solutions is required.
• Experience with virtual bank account / Virtual IBAN setup and integration is required.
• Experience integrating payment, banking, fiat-to-crypto, and crypto-to-fiat providers.
• Experience building or integrating deposit, withdrawal, settlement, and reconciliation flows.
• Experience with wallet infrastructure, custody platforms, or blockchain payment providers.
• Experience with Fireblocks or similar institutional wallet/custody infrastructure is highly desirable.
• Strong understanding of transaction signing, wallet security, private-key/MPC concepts, and blockchain security.
• Experience with blockchain APIs, RPC providers, explorers, webhooks, and transaction monitoring.
• Strong backend development experience using Node.js/TypeScript, Python, Go, or similar technologies.
• Experience designing and consuming REST APIs and event-driven services.
• Experience with databases such as PostgreSQL/MySQL and distributed systems.
• Strong troubleshooting skills for failed, delayed, stuck, or incorrectly routed blockchain transactions.
• Experience working with fintech, payments, crypto, exchanges, wallets, or regulated financial services is strongly preferred.

Must Have

• Experience with Fireblocks or similar MPC/custody platforms.
• Experience with Solana/SPL tokens.
• Experience integrating crypto payment providers or exchanges.
• Experience with Chainalysis or other blockchain compliance/monitoring platforms.
• Experience with blockchain indexing and event processing.
• Experience with smart contract development using Solidity.
• Experience with AWS and cloud-native infrastructure.
• Experience working in fintech, payments, crypto, or regulated financial services.
• Experience building high-volume transaction processing systems.