Senior Data Scientist, First Line Risk Bay Area, CA, US

The Role: The First Line Risk Data Science team at Block helps our teams understand, measure, and manage the risks of building financial products that serve millions of customers. We turn complex control, customer, and product data into measurement systems that help teams identify emerging risks, evaluate control performance, and close the gaps that matter most. We’re looking for a Senior Data Scientist to build and scale control performance monitoring for new and existing controls. You’ll help develop our control monitoring platform as the central place for teams to understand risk exposure, investigate changes, and prioritize action. You’ll partner closely with risk, compliance, product, and engineering to build automated measurement into product governance, from defining risk guardrails before launch to monitoring risk outcomes and control effectiveness afterward. This role requires analytical rigor, hands‑on building, and exceptional product judgment. You'll own control performance monitoring across a portfolio of controls and products, a large, multi-workstream scope, and be accountable for the long-term health and quality of the metrics and monitoring modules you build. You’ll measure success by the decisions your work improves, the material monitoring gaps it closes, and the risk management impact it delivers. You WillDefine and maintain actionable control performance metrics and key risk indicators that connect control objectives, risk exposure, and customer outcomes to clear decisions for first line owners and compliance partners Investigate how controls work in practice, using source data and system behavior to measure coverage, enforcement, exceptions, and outcomes, and identify where instrumentation or evidence is incomplete Contribute scalable monitoring metrics and modules into our monitoring application, connecting metrics to risks and controls and helping teams identify emerging risks and prioritize the most consequential monitoring gaps Turn high-value one‑off analyses into reusable analytical modules and automated monitoring workflows that scale across controls and products Apply statistical judgment to define populations, cohorts, baselines, and thresholds, and calibrate monitoring to detect meaningful changes while managing false positives and data quality limitations Build repeatable solutions for product governance, including pre‑launch risk measurement plans, rollout guardrails, and post‑launch monitoring of control performance and risk outcomes Partner with internal users to understand their decisions and workflows, shape a monitoring roadmap, and measure the value of solutions through adoption and improvements in risk management Lead ambiguous initiatives from problem definition through delivery, aligning stakeholders on the vision, tradeoffs, ownership, and actions that monitoring should support Communicate findings and evidence limitations clearly to technical partners, control owners, compliance teams, and senior leaders, and contribute reusable methods and technical guidance for other data scientists You Have A bachelor's degree in statistics, data science, economics, computer science, or a similar quantitative field with 7+ years of relevant experience; a master's degree with 5+ years; or a PhD with 3+ years. A track record of leading analytical solutions from problem definition through production use and adoption, including multi-person or cross-team efforts Advanced proficiency in SQL and Python, including experience working with large datasets and building maintainable analytical code, reusable modules, and automated data workflows Strong statistical and analytical judgment, including experience with cohort analysis, experimentation, time series, or monitoring, and the ability to recognize selection bias, incomplete data, and misleading metrics Experience translating business, policy, or control objectives into measurement frameworks that help stakeholders assess performance and take action Strong product instincts for internal tools, including the ability to understand stakeholder needs, prioritize by impact, and evaluate whether a solution improves how teams work and manage risk Excellent judgment in ambiguous situations, with the ability to make practical tradeoffs, build stakeholder alignment, and execute across teams Clear written and verbal communication, with the ability to explain complex analytical findings, uncertainty, and recommendations to technical and nontechnical audiences Experience in financial technology, risk, compliance, or product governance, or demonstrated ability to learn complex domains and apply rigorous measurement to them Experience using AI tools to accelerate analysis and development, validate conclusions, and automate repeatable analytical work Technologies We Use and TeachStrong proficiency in Python and SQL. Comfort writing clean, organized, and testable code and contributing to software applications that implement data science and analytical artifacts in pipelines or front-ends. Solid understanding of probability and statistics, including A/B test design and evaluation, standard error calculations and statistical inference, and anomaly detection techniques and methods. Experience with Python visualization packages (e.g. matplotlib / plotly). Experience working with git or version control systems. Experience leveraging LLMs and engineering prompts to accelerate development or analyze non-quantitative data. Experience with data warehousing platforms (e.g., Snowflake, BigQuery). 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 an equal opportunity employer evaluating all employees and job applicants without regard to identity or any legally protected class. We will consider qualified applicants with arrest or conviction records for employment in accordance with state and local laws and “fair chance” ordinances. 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 a workplace that is fair and square? Check out ourI+D page. While there is no specific deadline to apply for this role, U.S. roles are typically open for an average of 55 days before being filled by a successful candidate. Please refer to the date listed at the top of this job page for when this role was first posted. Block takes a market-based approach to pay, and pay may vary depending on your location. U.S. locations are categorized into one of four zones based on a cost of labor index for that geographic area. The successful candidate’s starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions. These ranges may be modified in the future. To find a location’s zone designation, please refer to this resource. If a location of interest is not listed, please speak with a recruiter for additional information. Zone A: $198,000 — $297,000 USD Zone B: $188,100 — $282,100 USD Zone C: $178,200 — $267,400 USD Zone D: $168,300 — $252,500 USD Application Guidelines Candidates may submit up to 9 active applications within a 60-day period. Reapplications to the same role are accepted 90 days after a previous application has been reviewed. Use of AI in Our Hiring Process We may use automated AI tools to evaluate job applications for efficiency and consistency. These tools comply with local regulations, including bias audits, and we handle all personal data in accordance with state and local privacy laws. Contact us here with hiring practice or data usage questions. Every benefit we offer is designed with one goal: empowering you to do the best work of your career while building the life you want. Remote work, medical insurance, flexible time off, retirement savings plans, and modern family planning are just some of our offering. Check out our other benefits at Block. Block, Inc. (NYSE: XYZ) builds technology to increase access to the global economy. Each of our brands unlocks different aspects of the economy for more people. Squaremakes commerce and financial services accessible to sellers. Cash Appis the easy way to spend, send, and store money. Afterpayis transforming the way customers manage their spending over time. TIDALis a music platform that empowers artists to thrive as entrepreneurs. Bitkeyis a simple self-custody wallet built for bitcoin. Protois a suite of bitcoin mining products and services. Together, we’re helping build a financial system that is open to everyone.