Senior Market & Trading Data Engineer (Java)

As a Senior Market & Trading Data Engineer at OKX, you will join the team building and operating the core data platform that powers public market data and proprietary trading data across the business. You'll work end to end on a high-throughput system that captures data from global crypto exchanges, ingests trading events from internal desks, and provides reliable real-time and historical data products to trading, quantitative research, risk, and analytics teams.

What you'll do

• Build and operate high-throughput Java pipelines for public market data, including trades, best bid and offer (BBO), tickers, funding rates, and L2/full order-book data from exchange REST and WebSocket APIs.
• Build and operate pipelines for proprietary trading data, including orders, fills, positions, balances, risk, and other events delivered through Kafka and internal integrations.
• Own ingestion, parsing, normalization, sequencing, validation, recovery, storage, and data access, with a strong focus on correctness, reliability, and performance.
• Onboard new exchanges and internal data sources, handling authentication, rate limits, disconnects, resubscription, snapshots and deltas, protocol changes, schema evolution, reconciliation, and access control.
• Build real-time and historical data paths using technologies such as Chronicle Queue, Kafka, relational and time-series databases, Apache Iceberg, Parquet, and ClickHouse, owning schema design, partitioning, retention, and query performance.
• Develop and operate data-access services and APIs, including routing, service discovery, high availability, failover, authorization for proprietary data, and backward compatibility for downstream clients.
• Maintain platform stability through monitoring, alerting, capacity management, data-quality checks, reconciliation, incident response, and reproducible runbooks, participating in the on-call rotation and responding to PagerDuty incidents.
• Support trading desks, quantitative researchers, and analytics users with data access, source onboarding, query support, and Java/Python client libraries.
• Maintain and improve the existing production platform while delivering safe, incremental migrations toward Kafka, ClickHouse, Iceberg, and Kubernetes through parallel runs, reconciliation, and controlled cutovers.
• Use AI coding assistants and LLM tooling responsibly to accelerate development, debugging, and data operations, and help the team adopt effective AI-native workflows.

What you bring

• A Bachelor's degree or above in Computer Science, Engineering, or a related quantitative field.
• 5+ years of hands-on experience in software engineering, market-data engineering, trading systems, or data-platform engineering.
• Strong production Java performance-tuning skills, including JVM and concurrency fundamentals, profiling, garbage collection and allocation behavior, and diagnosing thread and I/O bottlenecks.
• Hands-on experience building and operating real-time pipelines or data-serving systems for exchange market data, tick/order-book data, or proprietary trading data such as orders, fills, positions, balances, and risk.
• Experience building and operating production streaming pipelines, ideally with Kafka.
• Strong command of real-time event correctness, including ordering and sequencing, duplicate and gap detection, offsets and checkpoints, restart recovery, replay and backfill, idempotency, backpressure, reconciliation, and data validation.
• Strong SQL skills and production experience with a time-series or analytical database such as ClickHouse, QuestDB, or InfluxDB, including data modeling, partitioning, retention design, and query-performance tuning at scale.
• Strong distributed-systems fundamentals, with depth in one or more of the following: data APIs, routing and service discovery, high availability and failover, failure recovery, authorization, or backward-compatible data and client contracts.
• An ownership and operational mindset, with a strong focus on correctness, monitoring, reconciliation, data quality, backfills, incident response, and documentation.
• Comfort participating in an on-call rotation and owning the investigation, mitigation, and prevention of production incidents.
• Experience maintaining or safely migrating a legacy production data system while keeping critical services available.
• Proactive use of AI tools in day-to-day engineering, with sound judgment around verification, security, and safety.
• Fluency in English and Chinese.

Nice to have

• Experience building exchange REST/WebSocket connectors or feed handlers, particularly for order-book snapshot/delta streams, sequence and gap recovery, or exchange protocol changes.
• Knowledge of market microstructure, electronic trading, tick-data platforms, or market-by-order/market-by-price data models.
• Hands-on experience with ClickHouse or a comparable analytical database; Iceberg/Parquet or a comparable lakehouse; gRPC/Protobuf; Kubernetes; or service-discovery tools such as etcd.
• Experience developing data-access APIs or client libraries.
• Python experience for supporting tooling, analytics, and data operations.
• Experience with batch processing for historical data, reconciliation, backfills, or analytics.
• Exposure to AI/ML tooling or data products for model training and research.
• Interest in learning Rust for performance-critical components.

What we offer

• Competitive total compensation package.
• Learning and development programs and education subsidy for employees' growth and development.
• Various team-building programs and company events.
• Wellness and meal allowances.
• Comprehensive healthcare schemes for employees and dependents.

About OKX

OKX is a leading crypto exchange and developer of OKX Wallet, giving millions access to crypto trading and decentralized applications, as well as a trusted platform for hundreds of large institutions seeking access to crypto markets. OKX operates globally across multiple offices, united by core principles of "We Before Me", "Do the Right Thing", and "Get Things Done", and is part of OKG, a group bringing blockchain value to users worldwide through products including OKX, OKX Wallet, and OKLink.