Senior/Staff Java Engineer, Fraud Risk

As a Senior or Staff Java Engineer on OKX's Fraud Risk team, you will design and develop high-scale, 24/7 backend microservices for real-time fraud detection and prevention. You will work closely with frontend, cross-functional teams, and business users to implement a full feature risk ecosystem spanning real-time monitoring, event streaming, A/B testing, and data science-driven solutions. This role offers early and significant technical impact within a leading crypto exchange serving millions of users and hundreds of institutions.

What you'll do

• Design and develop 24/7 high-scale APIs and distributed systems on Alicloud or AWS
• Own, monitor, and improve services in production
• Develop backend microservices for real-time fraudulent monitoring with highly configurable rules, event data stream ingestion, and advanced fraud-fighting capabilities
• Write unit tests, integration tests, and CI/CD scripts
• Develop and test high-quality product features spanning multiple product domains
• Work with engineering managers, architects, engineers, and QA to develop innovative solutions that meet market needs regarding functionality, performance, reliability, and realistic implementation schedules
• Be a technical leader; research and promote new technologies and tools
• Face and solve technical challenges around performance, fault-tolerance, security, and live production issues
• Influence every step of the service lifecycle, from design through deployment

What you bring

• Minimum 5+ years of software development experience
• A solid foundation in Java with deep understanding of JVM configuration optimisation strategies, tuning, IO, multi-threading, concurrency frameworks, common data structures, algorithms, and design patterns
• Strong CS fundamentals, solid knowledge of OOP/OOD and GoF design patterns
• Proficiency with Spring Framework (Spring Boot), Hibernate (or similar ORM), Maven, and Git
• Experience with MySQL, Oracle, and other databases, including in-depth understanding of transactions, locks, indexes, database and SQL optimisation, and design methods such as sub-database sub-table and leader/follower synchronization
• Familiarity with common middleware such as Kafka, ELK, and Hologres
• Deep understanding of the design principles of common caching systems such as Memcached and Redis, with ability to accurately choose caching solutions
• Good understanding of distributed system principles, including CAP, consistency, and idempotent operation
• Experience developing Web Services, SOA, REST APIs, Message Queue, and Distributed/Scalable Architectures
• Ability to work well in a team environment and drive cross-team solutions with complex dependencies
• Results-oriented, self-learner, problem solver with a can-do attitude
• Clear logic, quick thinking, and good communication skills
• Bilingual proficiency in Mandarin and English is highly preferred

Nice to have

• Expertise in or eagerness to develop expertise in the blockchain and cryptocurrency landscape, including understanding of speculators, traders, digital asset exchanges, blockchain money services businesses, and financial institutions
• Experience working in disruptive technology, successfully launching products in FinTech, eCommerce, SaaS, AdTech, or Digital Wallet businesses
• A track record of being strategic, analytical, and execution-oriented
• Familiarity with product management processes and tools
• Experience working with teams across different time zones

What we offer

• Competitive total compensation package
• Wellness and meal allowances
• Comprehensive healthcare schemes for employees and dependants
• Various team building programs and company events

About OKX

OKX is a leading crypto exchange and developer of OKX Wallet, providing millions with access to crypto trading and decentralized applications. It serves hundreds of large institutions seeking access to crypto markets and is backed by Proof of Reserves. OKX is part of OKG, a group bringing blockchain value to users globally through products including OKX, OKX Wallet, and OKLink.