Senior Machine Learning Engineer, Ads

Details

Reddit is hiring a senior Machine Learning Engineer to join the Ads organization and contribute to the full ML lifecycle for ad ranking, bidding, measurement, and optimization. The role is hands-on and spans research, model development, deployment, and production optimization. Teams within Ads include Ads Prediction, App Ads & Conversion Modeling, Ads Measurement Modeling, Ads Targeting & Retrieval, Advertiser Optimization, Ads Marketplace Quality, Ads ML Serving, Attribution & Identity, and the Ads Creative Effectiveness team, which works with LLMs/VLMs and generative models for creative prediction and recommendation.

Responsibilities

• Design, build, and deploy industrial-level machine learning models for problems in ad ranking, bidding, and optimization.
• Take full ownership of the ML lifecycle: ideation, research, building scalable serving systems, and maintaining models in production.
• Perform systematic feature engineering to transform raw, diverse data into high-quality features that improve model performance.
• Collaborate with product managers, data scientists, and engineers to translate business challenges into ML solutions.
• Improve reliability and stability of ML systems by building robust monitoring, alerting, and automated retraining pipelines.
• Research new algorithms, stay current with state-of-the-art ML techniques, and contribute to team strategy and roadmap.

Requirements

• Experience working in the Ads domain.
• At least 3-5+ years of end-to-end experience training, evaluating, and deploying machine learning models in production.
• Proficiency in one or more general-purpose programming languages (e.g., Python, Scala) and solid software development best practices.
• Hands-on experience with a major ML framework (e.g., TensorFlow, PyTorch) and deep understanding of core ML concepts and algorithms.
• Proven ability to work effectively with cross-functional teams (product managers, data scientists) to translate business needs into technical solutions.
• Track record of using machine learning to drive KPI improvements and solve complex, real-world problems.

Bonus

• Experience or interest in the advertising business and understanding customer needs.
• Advanced degree (MS/PhD) in a quantitative field.
• Familiarity with distributed systems and large-scale data processing technologies (e.g., Spark, Kafka).

Benefits and Compensation

• Base pay range (U.S.): $216,700 - $303,400 USD per year.
• Eligible for equity (restricted stock units) and, depending on position, may be eligible for commission.
• U.S.-based benefits include medical, dental, vision insurance, 401(k) with employer match, generous time off, and parental leave.
• Interview recordings/transcriptions may be used in select roles with opt-out options; candidate privacy policy provided.

Notes

• Reddit supports flexible work arrangements and allows remote work in countries where Reddit has a physical presence. Physical offices are available for those who wish to come in.