Machine Learning Engineer, Ads

Details

Reddit is a community of communities built on shared interests, passion, and trust. The Ads organization is hiring Machine Learning Engineers across multiple teams (Ads Measurement Modeling, Ads Targeting & Retrieval, Advertiser Optimization, Ads Marketplace Quality) to design and deploy large-scale ML systems that improve ad relevance, bidding, measurement, and advertiser outcomes.

Role description

As a Machine Learning Engineer on the Ads team, you will own the full ML lifecycle: research and modeling, feature engineering, building scalable serving systems, deploying models to production, and optimizing/monitoring models in production. Your work will directly impact ad ranking, bidding, measurement, and optimization across Reddit’s ads products.

Responsibilities

• Design, build, and deploy industrial-level machine learning models for ad ranking, bidding, and optimization.
• Take full ownership of the ML lifecycle from ideation and research to scalable serving and production maintenance.
• Perform systematic feature engineering to transform raw, diverse data into high-quality features that drive 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 monitoring, alerting, and automated retraining pipelines.
• Research new algorithms and stay up-to-date with state-of-the-art ML techniques; contribute to team strategy and roadmap.

Requirements

• 3+ years of end-to-end experience training, evaluating, and deploying machine learning models in production.
• Proficient in one or more general-purpose programming languages (e.g., Python, Scala) with solid software development best practices.
• Hands-on experience with a major ML framework (e.g., TensorFlow, PyTorch) and a 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 points

• Experience in the Ads domain or interest in advertising business/customer needs.
• Advanced degree (MS/PhD) in a quantitative field.
• Familiarity with distributed systems and large-scale data processing technologies (e.g., Spark, Kafka).
• Experience or interest in measurement, privacy-aware modeling, and ATT opt-out utility work.

Benefits & Pay Transparency

• Base pay range (US): $185,800 - $260,100 USD.
• Eligible for equity (RSUs) and, depending on role, possible commission.
• U.S.-based benefits include medical/dental/vision, 401(k) match, generous time off, and parental leave.
• Interviews in select roles/locations may be recorded/transcribed; candidates can opt out prior to interviews.

Teams mentioned

• Ads Measurement Modeling: focuses on proving ad value while ensuring privacy compliance (Modeled Identity, Modeled Conversions, ATT opt-out utility).
• Ads Targeting & Retrieval: builds large-scale offline and online retrieval systems to improve targeting.
• Advertiser Optimization: builds recommendations, forecasting, bidding/pacing algorithms and advertiser tools.
• Ads Marketplace Quality: works on auction/pricing optimization, supply optimization, and ad relevance.

Location & Work Policy

• Role listed as Remote - United States. Reddit also supports flexible on-site attendance at physical offices and remote applications in countries where Reddit has physical presence.