Senior Backend Engineer, Exchange Systems

About the Role

Polymarket is looking for a Senior Backend Engineer to join our DeFi Trading team and own core improvements to our exchange systems. You'll work across low-latency APIs, high-throughput data streams, and settlement-aware order state and with a specific focus on evolving our CLOB engine to be faster, safer, and more concurrent as the platform scales.

This role requires someone who can reason clearly about how on-chain transaction lifecycle, confirmations, reorgs, balances, approvals, and execution outcomes affect off-chain exchange state. The problems are deep, the stakes are real, and the work will be immediately visible in production.

What You'll Do

• Own the CLOB engine's critical path. Profile matching and orderbook hot paths, map settlement-sensitive state transitions, and drive improvements to latency, throughput, and async engine flow backed by benchmarks and production-grade evidence.

• Reduce lock contention without breaking correctness. Debug concurrency issues, design safer queueing and backpressure for orderbooks, and improve the system's ability to handle materially more markets and order flow with lower tail latency.

• Build for observability and safety. Instrument improvements with pprof, metrics, logs, and traces. Establish rollback guarantees and narrower critical paths that make production incidents easier to detect, diagnose, and resolve.