Responsibilities
- Design, develop, and optimize OKX Pay payment backend systems for high availability, concurrency, scalability, and reliability.
- Build QR and scan-to-pay functionality including payment-code generation, scan recognition, order creation, confirmation, state transitions, timeout handling, risk validation, and exception compensation.
- Implement transaction processing for orders, payments, clearing and settlement, reconciliation, refunds, and callback notifications.
- Build crypto and stablecoin payment capabilities covering on-chain transfers, transaction confirmation, address management, asset crediting, and payment-status synchronization.
- Diagnose complex production issues involving performance bottlenecks, data consistency, fund-security risks, and abnormal transaction scenarios.
- Improve architecture, code quality, monitoring, alerting, observability, and payment-system maintainability.
Requirements
- Solid Java development skills and fluency with Spring Boot and mainstream Java backend frameworks.
- Hands-on experience with payment-system flows including payment orders, state machines, callbacks, reconciliation, refunds, clearing and settlement, and exception compensation.
- Experience with scan-to-pay, acquiring, aggregated payments, merchant payments, wallet payments, or similar products.
- Ability to design reliable transaction paths, state transitions, idempotency, retry, and compensation mechanisms.
- Understanding of data consistency, transaction handling, deduplication, concurrency protection, risk validation, and fund security.
- Familiarity with crypto and stablecoin payments, on-chain transfers, transaction confirmation, address systems, Gas, and crediting confirmation.
- Ability to troubleshoot production issues using log analysis, tracing, performance optimization, and recovery techniques.
- Experience with stablecoin payments involving USDT or USDC is preferred.
- Experience with QR payments, merchant acquiring, payment gateways, cross-border payments, offline payments, account and ledger systems, or reconciliation systems is preferred.
- Familiarity with EVM, Tron, Solana, or other mainstream blockchain transaction and asset-transfer mechanisms is preferred.
- Understanding of payment risk control, anti-fraud, limits, allow/deny lists, KYC/KYT, and AML mechanisms is preferred.
Benefits
- Competitive total compensation.
- Comprehensive insurance coverage for employees and their dependants.
About OKX
At OKX, we believe that the future will be reshaped by Crypto, ultimately contributing to every individual's freedom. OKX began as a crypto exchange giving millions of people access to crypto trading and over time becoming among the largest platforms in the world. In recent years, we have developed one of the most connected Web3 wallets used by millions to access decentralized crypto applications (dApps). OKX is a trusted brand by hundreds of large institutions seeking access to crypto markets on a reliable platform that seamlessly connects with global banking and payments. In the last year, OKX has expanded into new markets including Australia, Brazil, Netherlands, Singapore and Turkey, with plans to launch in the US, Belgium and the UAE. We are deeply committed to shaping a fairer, more transparent and accessible society through blockchain technology. This is why we publish proof of reserves monthly, and continue to ship new innovative security features. We believe in good sportmanship and the pursuit to be better. You may see our OKX logo neatly fitted on the McLaren F1 cars, Manchester City FC team shirts, or at the Tribeca Film Festival celebrating artists and creators. Wherever you may find us, you will notice our pursuit of making our world more efficient, transparent, and connected. To learn more about OKX, download our app or visit: www.okx.com UK users follow: https://www.linkedin.com/company/okxuk/ Learn more about working at OKG, the business group developing OKX, our Digital Assets Exchange, our Web3 portal and blockchain ecosystems: bit.ly/WorkingatOKG