Senior Java Engineer, OKX Pay Smart Account Team
Core
Design, develop, and optimize high-concurrency, scalable payment backend systems for a crypto exchange, covering QR/scan-to-pay, transaction processing, and crypto/stablecoin payments.
Role type
Senior Java Backend Engineer (Payments)
Builds
Payment infrastructure, QR/scan-to-pay capabilities, transaction processing systems, and crypto/stablecoin payment flows.
Domain
Fintech / Cryptocurrency / Payments
Deliverable
production ML models | product features | infrastructure
Required skills
Java (Spring Boot), high-concurrency system design, payment state machines, reconciliation, idempotency, risk-control validation, log analysis, tracing, performance optimization
Preferred skills
stablecoin payment experience, QR/acquiring experience, ledger systems, blockchain fundamentals (EVM, Tron, Solana), risk/compliance awareness
Technologies
Java, Spring Boot
Responsibilities
Design and optimize payment backend systems; implement scan-to-pay functionality (QR generation, recognition, state transitions); build secure transaction processing and settlement systems; integrate crypto/stablecoin payments with traditional experiences; diagnose and resolve complex production issues; improve system architecture and observability
Seniority
Senior, hands-on IC