Staff ML Engineer - Predictive Systems & Ads

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As a Staff / Principal Machine Learning Engineer on the Ads Forecasting team, you will serve as a technical lead guiding the machine learning capabilities and production infrastructure that enable advertisers to estimate campaign performance, model budget/bid scenarios, and maximize return on ad spend. In this high-impact role, you will lead the development of models connecting inventory supply, audience availability, and response prediction with auction dynamics and marketplace simulation. You will drive modeling direction, establish evaluation standards, and mentor engineers building reusable production pipelines across ad planning and recommendation products.

Key Responsibilities

• Technical Direction & Scenario Modeling: Set technical direction and lead the execution of models that estimate how campaign outcomes change across alternative budgets, bids, audience targets, and creative assets.
• Inventory, Demand & Response Integration: Synthesize signals across available advertising inventory, user activity, marketplace competition, and response models to deliver accurate outcome predictions.
• Advanced Predictive Architecture: Implement probabilistic forecasting, hierarchical modeling, multitask learning, and transfer learning to address sparse segments, cold start, distribution shift, and delayed feedback.
• Quantification of Unrealized Opportunity: Partner with creative and ad delivery teams to build models that evaluate creative performance impact, showing advertisers potential gains in reach, efficiency, and value.
• Trustworthy Model Evaluation: Establish evaluation benchmarks covering numerical accuracy, calibration, prediction uncertainty, and cohort-level performance using temporal validation and off-policy evaluation techniques.
• Production Delivery & Technical Mentorship: Partner with engineering teams on reliable training, serving, and real-time monitoring infrastructure; conduct design/code reviews and mentor engineers across the organization.

Requirements

Machine Learning & Predictive Modeling Depth

• Track record of designing, shipping, and operating predictive ML systems in advertising, marketplace platforms, recommendation systems, search, or demand forecasting.
• Deep mathematical foundations in statistical learning, probability theory, and optimization applied to large-scale behavioral or transactional datasets.
• Domain expertise in one or more core areas: probabilistic/hierarchical forecasting, calibrated conversion/value prediction, multitask or transfer learning, delayed-feedback/survival modeling, or response modeling.
• Strong evaluation judgment—including segment-level performance, temporal validation, calibration metrics, and handling uncertainty under counterfactual conditions.

Software Engineering & Technical Leadership

• Strong software engineering skills with experience building and operating production ML pipelines and microservices.
• Demonstrated ability to lead complex, ambiguous technical initiatives, balance practical trade-offs, and mentor other engineers.

Preferred Qualifications

• Demand, Supply & Inventory Forecasting: Probabilistic time-series models, hierarchical/global forecasting, external-signal modeling, multi-horizon prediction.
• Auction & Investment Modeling: Auction simulation or replay, conditional win-rate and price models, bid/budget response curves, constrained optimization.
• Scenario & Counterfactual Evaluation: Off-policy evaluation, sensitivity analysis, uncertainty propagation, composition of multiple predictive models.
• Reach & Audience Estimation: Population and overlap estimation, probabilistic reach/frequency models, sampling correction, saturation modeling.
• Advanced Methods: Mixture-of-experts, distributional/quantile prediction, temporal sequence models, state-space models.

Total Rewards & Benefits

• Compensation & Equity: Base salary of $230,000 – $322,000 USD + Restricted Stock Unit (RSU) equity grants.
• Healthcare & Wellbeing: Comprehensive medical, dental, and vision insurance; family planning support; gender-affirming care; and mental health/coaching benefits.
• Retirement & Income Protection: 401(k) program with employer match, life insurance, and income replacement programs.
• Time Off & Work Culture: Flexible vacation policy, paid volunteer time off, global lifestyle reimbursements, and generous paid parental leave.