Staff Machine Learning Engineer, Predictive Systems

The Role

As a Staff Machine Learning Engineer on the Predictive Systems team, you will drive the technical strategy for ML and decisioning systems that address risk, fraud, and abuse across Block. Acting as a technical domain owner for Cash App, Square, and Afterpay, you will shape how AI solutions are architected, integrated, and operationalized. Your leadership ensures that risk management functions as an enabler for product velocity, allowing teams to deploy features rapidly while maintaining a trusted ecosystem.

You are accountable for the production lifecycle of these systems, orchestrating the convergence of data, features, models, and controls into scalable defenses. Operating at the ecosystem level, you will define durable abstractions and decisioning patterns that standardize risk strategies across diverse domains. You will also influence the roadmap of Block's core ML infrastructure, ensuring the platform evolves to meet the requirements of complex, high-volume decisioning workloads.

You Will

• Act as a technical lead across multiple Risk ML engineering teams, setting direction for how ML and AI solutions are applied to fraud, abuse, and risk decisioning.
• Design and evolve real-time and batch ML systems that leverage Block's core ML platforms to deliver scalable risk solutions.
• Drive architectural decisions around feature usage, contextual signals, and ML-driven controls in partnership with modeling, product, and platform teams.
• Translate ambiguous risk problems into clear technical strategies and execution plans.
• Lead cross-team efforts to integrate new data sources, signals, and event hooks into production risk systems.
• Establish standards for data quality, observability, and correctness for ML inputs and decisions.
• Provide technical leadership during emerging threat and SEV scenarios, guiding rapid mitigation while preserving long-term system health.
• Influence ML and AI engineering practices across Risk, improving consistency, reliability, and velocity.

You Have

• Extensive experience designing and leading large-scale ML systems with broad organizational impact.
• A proven ability to set technical vision and drive alignment across multiple teams and disciplines.
• Deep understanding of ML systems, data platforms, and real-time decisioning at scale.
• Strong judgment in navigating complex tradeoffs involving risk, trust, and product velocity.
• A history of mentoring senior engineers and developing future technical leaders.
• A systems-level mindset and a bias toward durable, high-leverage solutions.

Technologies We Use and Teach

• Python, Java and Kotlin
• Tensorflow and PyTorch
• AWS, Databricks and Kubernetes
• MySQL, DynamoDB, Kafka, Spark

 

 

We're working to build a more inclusive economy where our customers have equal access to opportunity, and we strive to live by these same values in building our workplace. Block is a proud equal opportunity employer. We work hard to evaluate all employees and job applicants consistently, based solely on the core competencies required of the role at hand, and without regard to any legally protected class. We believe in being fair, and are committed to an inclusive interview experience, including providing reasonable accommodations to disabled applicants throughout the recruitment process. We encourage applicants to share any needed accommodations with their recruiter, who will treat these requests as confidentially as possible. Want to learn more about what we're doing to build an inclusive workplace? Check out our Inclusion & Diversity page

 

Full-time employee benefits include the following:

• Healthcare coverage (Medical, Vision and Dental insurance)
• Health Savings Account and Flexible Spending Account
• Retirement Plans including company match
• Employee Stock Purchase Program
• Wellness programs, including access to mental health, 1:1 financial planners, and a monthly wellness