Senior Data Scientist

Circle Internet Financial • San Francisco, CA

3d • $152,500 - $205,000 • Remote

About The Position

As a Senior Data Scientist on Circle’s Fraud Analytics team, you will own the prediction side of the fraud loop. You will turn fraud labels into features and models, measure model accuracy, and help Circle move from vendor scores to in-house models as the company expands the customers and payment methods it serves. You will collaborate with Fraud Strategy, Fraud Operations, Risk Engineering, and Compliance.

Requirements

• At least 5 years of experience in data science or applied machine learning in fraud, risk, or financial crime.
• Advanced Python and SQL skills, and experience with XGBoost, LightGBM, or similar tools.
• Experience building models with sparse, delayed, or biased labels, including cold start, reject inference, and chargeback lag.
• Strong statistical skills, including anomaly detection, graph or network methods, experimentation, and threshold optimization.
• Experience taking models to production and monitoring them.
• Clear communication with technical and non-technical partners.
• Comfort working through ambiguity and limited historical data.

Nice To Haves

• Fintech, payments, crypto, or card fraud experience, including chargebacks and disputes.
• Experience with device intelligence, behavioral signals, or consortium data.
• Familiarity with blockchain analytics, AML, and KYC.
• Experience evaluating LLM or agent-based review workflows.

Responsibilities

• Build and evaluate fraud models for onboarding, login, account changes, and money movement, targeting risks such as account takeover, scams, money mules, and stolen or synthetic identity.
• Evaluate third-party risk signals and design the transition from vendor models to Circle models, from shadow mode through production.
• Define label taxonomies and data requirements with Fraud Operations and Risk Engineering so events, decisions, and outcomes—including missed fraud—become training data.
• Design holdout and exploration sampling to measure false negatives and the rate at which legitimate customers are wrongly blocked.
• Track fraud rate, dispute rate, fraud loss rate, and precision across customer segments.
• Help set thresholds against an agreed loss budget.
• Work with Fraud Strategy to tune thresholds and rules and respond to emerging attacks.
• Backtest models, monitor drift, and retrain models on Circle’s fraud platform.
• Help build AI agent workflows for transaction review, fraud-ring analysis, and rule drafting, and evaluate their accuracy against human labels.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed