Block

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 Block lends, moves money, and screens for financial crime at enormous scale, and one bad model can mean millions in credit losses, suspicious activity that goes unreported, or a fair lending violation. Model Risk Management is the independent function that decides whether a model is sound enough to put in front of customers and regulators. The failures that matter rarely announce themselves: a model can clear every headline metric and still be broken underneath. It can pass clean at launch and then quietly drift as the population shifts, until the loss it was supposed to prevent surfaces months later. The hard part is finding what looks right and is wrong, then proving it well enough to hold up under questioning. Much of the work arrives under-specified, so you scope it into a defensible plan, ask the questions that surface the real requirements, and defend your tradeoffs to the people who built the model you are challenging. The same scrutiny you apply to models applies to AI. We build the tooling that lets a lean team validate at scale, so you critically evaluate what it produces and own the evaluation that confirms its output is reliable enough to act on. That work matters most for the GenAI and agentic systems most teams have not figured out how to oversee yet. As a senior individual contributor, you lead through technical depth and cross-team scope, and you partner widely across the organization. You work with the first-line modelers you challenge, the Legal, Compliance, and fair-lending teams who rely on your analysis, and the auditors and bank partners who carry it into regulatory engagements. This role is remote-friendly within approved US locations. You Will Independently challenge model owners across lending, fraud, and AML: reproduce their results, set and defend the acceptance thresholds, and own the call on whether a model is sound. Hunt the silent errors that make metrics lie, and prove them out before they reach production. Choose evaluation that holds up under real conditions: rare events, shifting populations, and drift that only shows up after launch. Work hands-on in codebases you did not write, learning the data, configs, and conventions, and ship production code in the tooling you build to validate them. Build the agentic validation tooling the team depends on, orchestrating agents that run in parallel. Reason about ML systems end to end — how features, training, serving, monitoring, and scale fit together — to evaluate and challenge an owner's design. Tie explainability and fair-lending findings on consumer credit models back to the model and product decisions that follow. Help define how Block validates the systems at the frontier of production AI, setting standards where none exist yet. You Have A quantitative degree or equivalent experience, and senior-IC depth building or validating models in a high-stakes domain such as credit, fraud, or financial crime. Command of effective-challenge methodology: reproduction, conceptual-soundness review, benchmarking, stress testing, and outcomes analysis, with an eye for how a model holds up after launch and where its assumptions break. Deep applied ML and statistics across model families, from regression and tree ensembles to deep learning, with sound judgment about evaluation, calibration, and generalization. Experimentation and statistical rigor: holdout and experiment design, reasoning about uncertainty, and evaluating a model beyond aggregate accuracy. Solid software and data engineering: production-quality Python, SQL on large datasets, and reproducible, tested code. Fluency with modern AI: building with LLMs and agentic tools, and the judgment to know when their output can be trusted. Familiarity with model risk management frameworks and fair-lending standards, with the specifics learnable on the job. The communication to explain and defend your conclusions to model owners and senior stakeholders, and the independence to operate under ambiguity. Technologies We Use and Teach Python (NumPy, Pandas, scikit-learn, LightGBM, XGBoost, PyTorch) AI dev tools: Claude Code, Cursor, Copilot; agent skills and frameworks for building LLM-powered tooling MLflow / Databricks; Prefect on GCP Vertex AI Snowflake and cloud object storage GitHub and CI (ruff, pytest) Jira and Linear GCP and AWS 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: $189,000—$283,600 USD Zone B: $179,600—$269,400 USD Zone C: $170,100—$255,100 USD Zone D: $160,700—$241,100 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. 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. Privacy Policy

It all started with an idea at Block in 2013. Initially built to take the pain out of peer-to-peer payments, Cash App has gone from a simple product with a single purpose to a dynamic ecosystem, developing unique financial products, including Afterpay/Clearpay, to provide a better way to send, spend, invest, borrow and save to our 50+ million monthly active customers. We want to redefine the world’s relationship with money to make it more relatable, instantly available, and universally accessible. Today, Cash App has thousands of employees working globally across office and remote locations, with a culture geared toward innovation, collaboration and impact. We’ve been a distributed team since day one, and many of our roles can be done remotely from the countries where Cash App operates. No matter the location, we tailor our experience to ensure our employees are creative, productive, and happy. The Role As a Senior Data Scientist focusing on AI & Model Risk, you will lead and coordinate AI risk assessments for Generative AI and Large Language Model use cases, applying Model Risk Management principles to ensure safe, compliant, and responsible deployment. This role sits at the intersection of Model Risk Management and AI Governance, with close coordination with Information Security, Compliance, and Legal stakeholders. You will tackle complex and ambiguous challenges, applying sound judgment to select appropriate methodologies and drive risk-based decisions with minimal day-to-day oversight. You will partner with senior stakeholders across Risk, Engineering, Legal, Compliance, and Information Security to drive assessment outcomes and continuously strengthen governance practice. This role puts you at the center of an innovative team within SFS that's actively shaping how AI risk management works in practice; Operationalizing principles into processes that enable safe, effective AI deployment. If you're excited by the challenge of shaping how AI gets deployed safely and responsibly in financial services, this is the place to be. You Will Lead end-to-end AI Risk Assessments for generative AI and LLM use cases across the Bank; Embedding in Block's enterprise-wide GenAI review process, coordinating cross-functional SMEs (Legal, Compliance, InfoSec, Data Governance, MRM, ERM, BRC, TPRM, Financial Crimes), and managing timelines to ensure reviews are completed within SLA. Review AI system design and documentation; Including retrieval sources, assumptions, limitations, fallback plans, guardrail configurations, and change management procedures — across banking use cases such as fraud detection, BSA/AML compliance, credit decisioning, and customer-facing applications, ensuring governance controls are commensurate with each use case's risk profile. Assess pre-deployment testing for adequacy inclusive of output integrity, hallucination detection, boundary and edge case testing, ethical and safety guardrails, bias testing, A/B testing, volume testing, and UAT — designing and conducting independent testing as needed. Evaluate ongoing monitoring plans for comprehensiveness - including accuracy, hallucination rates, drift detection, sensitive data controls, reliability metrics, CSAT, acceptable performance ranges, and documented remediation procedures. Develop and maintain templates, tools, and procedures to support the effectiveness and scalability of the AI Risk Governance Program. Monitor the evolving regulatory landscape for AI in banking — including FFIEC IT Examination Handbook standards, FDIC Financial Institution Letters, interagency statements, and the anticipated RFI on AI model risk management referenced in SR 26-2 — and incorporate emerging guidance into the AI risk governance program; support SFS's response to regulatory inquiries as needed. You Have A minimum of 5 years of related experience with a Bachelor’s degree in a quantitative field; or 3 years and a Master’s degree; or a PhD without experience; or equivalent work experience in risk management, model risk management, or AI risk management Proficiency in Python or similar languages for evaluating AI system behavior, writing test scripts, or analyzing model outputs Strong understanding of generative AI architectures; Including LLMs, transformer models, RAG systems, and agentic AI, plus hands-on experience interacting with and critically evaluating these systems, sufficient to assess design decisions, output quality, and limitations Understanding of interagency model risk management principles, including SR 26-2 Knowledge of AI testing methodologies, ex. functional testing, bias testing, adversarial testing, and performance monitoring plus familiarity with data privacy and security principles (encryption, access controls, data classification) Excellent written and verbal communication and the ability to translate complex technical AI concepts for non-technical stakeholders, senior management, and regulators Strong analytical judgment with the ability to manage multiple concurrent assessments, prioritize effectively, and drive risk-based decisions with minimal day-to-day oversight Nice to Have Master's degree in AI/ML, Cybersecurity, Data Science, or related field Familiarity with AI governance frameworks (NIST AI RMF, ISO 42001, or equivalent) and the FFIEC IT Examination Handbooks Experience with AI governance tools and platforms (model registries, monitoring dashboards, risk scoring systems) Experience with explainability tools (SHAP, LIME, attention visualization) Certifications: CRISC, PRM, FRM, or AI-specific certifications such as NIST AI RMF practitioner or ISO 42001 Lead Implementer Prior experience in a second-line-of-defense or internal audit role at a bank or financial institution Experience developing AI risk governance frameworks in environments where prescriptive regulatory guidance does not yet exist Technologies We Use and Teach Block is investing heavily in AI, and our workflows are evolving accordingly. This creates a rare opportunity to work with emerging systems as they take shape, both leveraging them in practice and influencing how they are designed. The team is at the forefront of defining risk governance in an AI-first environment, with the goal of setting new industry standards. 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 our I+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: $163,600—$225,000 USD Zone B: $155,400—$213,700 USD Zone C: $147,300—$202,500 USD Zone D: $139,000—$191,200 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. 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. Privacy Policy

It all started with an idea at Block in 2013. Initially built to take the pain out of peer-to-peer payments, Cash App has gone from a simple product with a single purpose to a dynamic ecosystem, developing unique financial products, including Afterpay/Clearpay, to provide a better way to send, spend, invest, borrow and save to our 50+ million monthly active customers. We want to redefine the world’s relationship with money to make it more relatable, instantly available, and universally accessible. Today, Cash App has thousands of employees working globally across office and remote locations, with a culture geared toward innovation, collaboration and impact. We’ve been a distributed team since day one, and many of our roles can be done remotely from the countries where Cash App operates. No matter the location, we tailor our experience to ensure our employees are creative, productive, and happy. The Role As a Senior Data Scientist focusing on AI & Model Risk, you will lead and coordinate AI risk assessments for Generative AI and Large Language Model use cases, applying Model Risk Management principles to ensure safe, compliant, and responsible deployment. This role sits at the intersection of Model Risk Management and AI Governance, with close coordination with Information Security, Compliance, and Legal stakeholders. You will tackle complex and ambiguous challenges, applying sound judgment to select appropriate methodologies and drive risk-based decisions with minimal day-to-day oversight. You will partner with senior stakeholders across Risk, Engineering, Legal, Compliance, and Information Security to drive assessment outcomes and continuously strengthen governance practice. This role puts you at the center of an innovative team within SFS that's actively shaping how AI risk management works in practice; Operationalizing principles into processes that enable safe, effective AI deployment. If you're excited by the challenge of shaping how AI gets deployed safely and responsibly in financial services, this is the place to be. You Will Lead end-to-end AI Risk Assessments for generative AI and LLM use cases across the Bank; Embedding in Block's enterprise-wide GenAI review process, coordinating cross-functional SMEs (Legal, Compliance, InfoSec, Data Governance, MRM, ERM, BRC, TPRM, Financial Crimes), and managing timelines to ensure reviews are completed within SLA. Review AI system design and documentation; Including retrieval sources, assumptions, limitations, fallback plans, guardrail configurations, and change management procedures — across banking use cases such as fraud detection, BSA/AML compliance, credit decisioning, and customer-facing applications, ensuring governance controls are commensurate with each use case's risk profile. Assess pre-deployment testing for adequacy inclusive of output integrity, hallucination detection, boundary and edge case testing, ethical and safety guardrails, bias testing, A/B testing, volume testing, and UAT — designing and conducting independent testing as needed. Evaluate ongoing monitoring plans for comprehensiveness - including accuracy, hallucination rates, drift detection, sensitive data controls, reliability metrics, CSAT, acceptable performance ranges, and documented remediation procedures. Develop and maintain templates, tools, and procedures to support the effectiveness and scalability of the AI Risk Governance Program. Monitor the evolving regulatory landscape for AI in banking — including FFIEC IT Examination Handbook standards, FDIC Financial Institution Letters, interagency statements, and the anticipated RFI on AI model risk management referenced in SR 26-2 — and incorporate emerging guidance into the AI risk governance program; support SFS's response to regulatory inquiries as needed. You Have A minimum of 5 years of related experience with a Bachelor’s degree in a quantitative field; or 3 years and a Master’s degree; or a PhD without experience; or equivalent work experience in risk management, model risk management, or AI risk management Proficiency in Python or similar languages for evaluating AI system behavior, writing test scripts, or analyzing model outputs Strong understanding of generative AI architectures; Including LLMs, transformer models, RAG systems, and agentic AI, plus hands-on experience interacting with and critically evaluating these systems, sufficient to assess design decisions, output quality, and limitations Understanding of interagency model risk management principles, including SR 26-2 Knowledge of AI testing methodologies, ex. functional testing, bias testing, adversarial testing, and performance monitoring plus familiarity with data privacy and security principles (encryption, access controls, data classification) Excellent written and verbal communication and the ability to translate complex technical AI concepts for non-technical stakeholders, senior management, and regulators Strong analytical judgment with the ability to manage multiple concurrent assessments, prioritize effectively, and drive risk-based decisions with minimal day-to-day oversight Nice to Have Master's degree in AI/ML, Cybersecurity, Data Science, or related field Familiarity with AI governance frameworks (NIST AI RMF, ISO 42001, or equivalent) and the FFIEC IT Examination Handbooks Experience with AI governance tools and platforms (model registries, monitoring dashboards, risk scoring systems) Experience with explainability tools (SHAP, LIME, attention visualization) Certifications: CRISC, PRM, FRM, or AI-specific certifications such as NIST AI RMF practitioner or ISO 42001 Lead Implementer Prior experience in a second-line-of-defense or internal audit role at a bank or financial institution Experience developing AI risk governance frameworks in environments where prescriptive regulatory guidance does not yet exist Technologies We Use and Teach Block is investing heavily in AI, and our workflows are evolving accordingly. This creates a rare opportunity to work with emerging systems as they take shape, both leveraging them in practice and influencing how they are designed. The team is at the forefront of defining risk governance in an AI-first environment, with the goal of setting new industry standards. 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 our I+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: $163,600—$225,000 USD Zone B: $155,400—$213,700 USD Zone C: $147,300—$202,500 USD Zone D: $139,000—$191,200 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. 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. Privacy Policy