Senior Backend Engineer, Trust & Safety

About PolymarketPolymarket is the world's largest prediction market platform. We enable individuals to express views on real-world events by trading on outcomes across politics, economics, sports, culture, and current affairs. Built as a peer-to-peer marketplace with no centralized "house," Polymarket aggregates diverse opinions into transparent, market-based probabilities that reflect collective expectations about the future.We're growing fast — both in terms of volume ($21B traded in 2025) and adoption as an alternative news source. Our ambition is to become a ubiquitous beacon of truth in global media and we need your help adding fuel to the fire.About the RolePolymarket is looking for a Backend Engineer to build the detection, monitoring, and case-management systems that keep our platform compliant and safe at scale.This role partners closely with Compliance, Risk, and Legal to translate regulatory requirements into engineering systems that protect the platform and its users, with high ownership and direct impact on Polymarket's risk posture.What You'll DoDesign and build detection, monitoring, and case-management systems to meet AML/BSA, KYC/EDD, and sanctions-screening obligations at scaleBuild on or integrate with trade-surveillance and case-management platforms (e.g., Eventus, Palantir) and structure audit-grade data pipelines (tiered storage, long-term retention in S3) for compliance and financial-crimes reviewModel and reconcile financial data (FinOps, ledger reconciliation) to ensure auditability and accuracy of money-movement recordsTranslate regulatory requirements into engineering systems — alerting, case queues, investigative reporting — in close partnership with Compliance, Risk, and LegalDevelop real-time risk decisioning and transaction-monitoring systems to detect and respond to financial crimeWork closely with engineers across the platform to keep Trust & Safety systems tightly integrated with the broader exchangeWhat We're Looking ForBackend engineering experience building detection, monitoring, or case-management tooling for AML/BSA, KYC/EDD, or sanctions-screening obligations at scaleExperience integrating or building on trade-surveillance and case-management platforms (e.g., Eventus, Palantir) and structuring audit-grade data pipelinesComfortable modeling and reconciling financial data (FinOps, ledger reconciliation) for auditability and accuracyTrack record partnering directly with Compliance, Risk, and Legal teams to translate regulatory requirements into engineering systemsBackground in risk/fraud or compliance-technology engineering at a fintech or crypto exchange(Plus) Experience building real-time risk decisioning or transaction-monitoring systems at scaleBenefitsCompetitive salary & equityUnlimited PTOFull Health, Vision, & Dental coverage401k matchHardware setup: new MacBook Pro, big display, & accessoriesPay TransparencyBase salary range: $250,000 to $500,000 annually, plus equity and benefits.This range reflects a good-faith estimate for this position. Experience levels vary widely within a title here, so please reach out even if your expectations fall outside it. We're always happy to chat.LocationNew YorkEmployment TypeFull timeLocation TypeOn-siteDepartmentEngineeringEngineering, US