Staff Data Scientist, Credit Policy (Square Financial Services)

Block builds simple, powerful tools that make progress towards an economy that’s truly open to all.

Each of our brands unlocks different aspects of the economy for more people. Square makes commerce and financial services accessible to sellers. Cash App is the easy way to spend, send, and store money. Afterpay is transforming the way customers manage their spending over time. TIDAL is a music platform that empowers artists to thrive as entrepreneurs. Bitkey is a simple self-custody wallet built for bitcoin. Proto is a suite of bitcoin mining products and services. Together, we’re helping build a financial system that is open to everyone. Join us.

The Role

The Credit and Lending team is responsible for the predictive intelligence that underpins Block’s primary capital-intensive products. These products unlock unique access to credit for our customers, many of whom are otherwise underbanked and underserved by the traditional financial system. As a member of the Credit Policy team within Square Financial Services (SFS), you will occupy a high-leverage role at the intersection of regulated banking and advanced autonomous systems. This position requires end-to-end ownership of credit policy, from the evaluation of novel data signals to the design of the decisioning logic that drives Block’s top-line growth. Beyond policy design, this role carries core responsibility for credit policy governance: ensuring that policy changes and experiments are rigorously designed, reviewed, documented, monitored, and reported in line with the expectations of a regulated bank.

Our credit products are material drivers of the company’s profitability and are frequently highlighted in executive reviews and quarterly earnings reports. We are seeking a scientifically-minded contributor capable of delivering extraordinary individual leverage to expand our underwriting capabilities into previously untapped segments through pragmatic policy evolution and advanced modeling techniques.

You Will

• Apply a rigorous scientific mindset to the challenge of underwriting new customer segments, involving the evaluation of alternative external data sources and the design of new policy strategies to expand access while protecting the portfolio.
• Own credit policy governance and reporting: maintain policy documentation, change logs, and approval artifacts, and deliver recurring portfolio performance and policy-impact reporting to credit risk committees, senior leadership, and bank oversight functions.
• Propose and design experiments for credit products — champion/challenger tests, randomized holdouts, and staged rollouts across approval, limit, and pricing strategy — with clear hypotheses, success metrics, guardrails, and loss-exposure budgets.
• Review experiment designs proposed by partner teams, assessing statistical rigor, sample sizing, risk exposure, fair lending considerations, and alignment with credit policy and regulatory requirements before launch.
• Form policy guidelines and frameworks — risk appetite thresholds, approval and limit standards, and concentration limits — that enable credit portfolios to scale responsibly while meeting growth, loss, and profitability objectives.
• Partner with Risk Management, Compliance and Internal Audit teams to ensure policy changes meet governance standards and are well documented and exam-ready.
• Support team members in ad-hoc and scheduled updates to existing policies and strategies, and help troubleshoot issues in a real-time production environment.
• Operate effectively within the framework of a regulated bank (SFS), balancing rapid innovation with the requirements of safety, soundness, and compliance.

Qualifications

• 8+ years of related experience with a Bachelor's degree; or 6+ years and a Master's degree; or a PhD with 3+ years experience; or equivalent experience
• A degree in a technical field (e.g., Computer Science, Mathematics, Statistics, Physics, or Engineering). We have a strong preference for candidates with a demonstrated track record of scientific research or an advanced degree.
• Demonstrated experience in credit policy governance at a bank, fintech, or consumer/small business lender — including documenting and approving policy changes, preparing materials for credit or risk committees, and supporting regulatory exams and internal audits.
• Hands-on experience proposing, designing, and reviewing experiments for credit products (e.g., champion/challenger tests, randomized holdouts, and staged rollouts on approval, line assignment, or pricing), including power and sample sizing, loss-exposure guardrails, and decision-ready readouts.
• A track record of building and owning portfolio monitoring and reporting — KPIs, early-warning indicators, vintage and roll-rate analysis — used to steer credit policy and communicate performance to leadership.
• Experience translating business objectives into credit policy guidelines, such as risk appetite thresholds, approval and limit standards, and concentration limits, that allow portfolios to scale while staying within loss and profitability targets.
• Familiarity with regulatory expectations for credit products is strongly preferred.
• Strong quantitative intuition and data visualization skills, with a proven ability to conduct sophisticated ad-hoc and exploratory analysis.
• Strong proficiency in SQL and Python preferred, including the ability to contribute across the analytical stack—from data pipelines to production-ready policy logic.
• The versatility to communicate clearly with both technical and non-technical audiences, particularly in the context of high-visibility projects and senior stakeholders.
• A pragmatic approach to problem-solving, with a willingness to utilize whichever tool is most appropriate for the situation while balancing complex business, technical, and regulatory constraints.