Senior / Staff Engineer, DEX Trading System

OKX will be prioritising applicants who have a current right to work in Singapore, and do not require OKX's sponsorship of a visa Who We Are At OKX, we believe that the future will be reshaped by crypto, and ultimately contribute to every individual's freedom. OKX is a leading crypto exchange, and the developer of OKX Wallet, giving millions access to crypto trading and decentralized crypto applications (dApps). OKX is also a trusted brand by hundreds of large institutions seeking access to crypto markets. We are safe and reliable, backed by our Proof of Reserves. Across our multiple offices globally, we are united by our core principles: We Before Me , Do the Right Thing , and Get Things Done . These shared values drive our culture, shape our processes, and foster a friendly, rewarding, and diverse environment for every OK-er. OKX is part of OKG, a group that brings the value of Blockchain to users around the world, through our leading products OKX, OKX Wallet, OKLink and more. About the Opportunity We are looking for a seasoned backend engineer to design, build, and scale the backend systems powering OKX’s DEX trading products. You will own critical parts of the trading lifecycle—from quote discovery and order management to transaction submission, execution tracking, and reconciliation. Working closely with product, frontend, smart contract, and infrastructure teams, you will deliver secure, reliable trading experiences across multiple blockchain ecosystems. This is a hands-on engineering role with meaningful architectural ownership and opportunities to grow into technical leadership. What You’ll Be Doing • Design and develop backend services for quote aggregation, order management, transaction orchestration, and execution tracking. • Build reliable integrations with DEX protocols, liquidity sources, blockchain RPC providers, and indexing services. Define clear order and transaction state models, with robust handling of retries, duplicate requests, partial failures, and recovery. • Ensure trading services remain reliable under high concurrency, traffic spikes, and degraded external dependencies. • Implement appropriate rate limiting, concurrency controls, resource isolation, and graceful degradation. • Optimize database access, transaction boundaries, caching, and asynchronous processing. Establish monitoring, alerting, load testing, and incident-response practices for critical trading flows. • Support trading workflows across multiple blockchain ecosystems. Handle transaction submission, confirmation tracking, failed or dropped transactions, and chain reorganizations. • Build data synchronization and reconciliation mechanisms to maintain consistency between backend records and on-chain execution. • Translate product requirements into practical technical designs and production-ready services. • Own features through implementation, testing, rollout, and post-launch operation. What We Look For In You • 5+ years of professional backend engineering experience, including ownership of production systems. • Strong proficiency in Java and its backend ecosystem. Solid understanding of concurrency, distributed systems, relational databases, caching, and messaging systems. • E xperience building high-availability services and diagnosing performance or reliability issues in production. • Understanding of blockchain transactions, smart contract interactions, and common DeFi trading mechanisms. • Ability to independently drive a feature from technical design through production deployment. Strong ownership, sound engineering judgment, and effective cross-functional communication. Perks & Benefits • Competitive total compensation package • L&D programs and Education subsidy for employees' growth and development • Vari