Staff Applied Machine Learning Engineer

Responsibilities

• Build and operate real-time and batch ML decisioning systems for payment fraud, scams, identity and account integrity, merchant and marketplace risk, and abuse prevention
• Integrate behavioral, graph, device, network, event-stream, and third-party signals into low-latency model serving and decision APIs
• Own the production lifecycle for risk decisions, including data contracts, feature quality, monitoring, and incident response
• Develop feedback loops and AI-assisted workflows for triage, investigation support, and alert clustering
• Partner with modelers, analysts, product, compliance, and operations to balance fraud losses and customer access

Requirements

• 12+ years building and operating production software and ML systems
• Deep expertise in fraud/risk domains such as payment fraud, identity, or marketplace risk
• Strong production ML judgment across feature pipelines, model serving, and monitoring
• Experience using AI-assisted engineering tools for high-stakes systems

Preferred Qualifications

• Experience with graph-based fraud detection or behavioral sequence models
• Experience building fraud operations tooling for triage or case management
• Experience with regulated financial services, model governance, or auditability

About the Company

Block builds simple, powerful tools that make progress towards an economy that’s truly open to all through brands like Square, Cash App, Afterpay, and TIDAL.