Senior Machine Learning Engineer, Risk Modeling

Join Block’s Risk Machine Learning organization to build end-to-end machine learning systems that detect, prevent, and reduce fraud and abuse across Cash App and Square. The role covers problem definition, modeling, deployment, monitoring, iteration, technical leadership, and production ML reliability.

Responsibilities

• Partner with product, engineering, data science, policy, and operations to design and productionize ML-driven risk solutions at scale
• Own end-to-end machine learning systems from problem definition and modeling through deployment, monitoring, and iteration
• Lead technical decision-making within workstreams and influence ML strategy and planning
• Build tooling and processes that improve the speed, reliability, and impact of the ML development lifecycle
• Apply advanced modeling techniques and third-party data sources to improve detection and decision-making
• Investigate emerging fraud, abuse, and risk patterns to inform product safeguards and policy
• Collaborate with ML platform and engineering teams to ensure models operate reliably in real time and at scale

Requirements

• 8+ years of industry experience in machine learning, applied AI, or related fields
• Bachelor’s degree in a quantitative field; Master’s or PhD preferred
• Experience independently designing, deploying, and maintaining ML solutions in production
• Familiarity with tree-based models, deep learning, transfer learning, or reinforcement learning
• Experience influencing technical direction and collaborating with cross-functional partners at scale
• Strong communication skills, sound judgment, and an ownership mindset
• Curiosity and alignment with Block’s mission of economic empowerment

Benefits

• Remote work
• Medical insurance
• Flexible time off
• Retirement savings plans
• Modern family planning