Machine Learning Engineer, Ads

Details

Reddit is a community of communities built on shared interests, passion, and trust and is home to open and authentic conversations. With 100,000+ active communities and ~101M+ daily active unique visitors, Reddit is one of the internet’s largest sources of information. Reddit offers flexible work arrangements and candidates can apply to work remotely in countries where Reddit has a physical presence.

Team Description

We are hiring across multiple Ads teams including Ads Measurement Modeling, Ads Targeting & Retrieval, Advertiser Optimization, Ads Marketplace Quality, and Ads Creative Effectiveness. Highlights:

• Ads Measurement Modeling: works on proving the value of Reddit Ads, addressing signals, privacy, and identity (Modeled Identity, Modeled Conversions, ATT opt-out utility).
• Ads Targeting and Retrieval: builds large-scale ML systems for contextual and behavioral targeting, offline and online retrieval systems.
• Advertiser Optimization: focuses on recommendations, forecasting, bidding/pacing (TCPA, TROAS), marketplace dynamics, and advertiser-facing products.
• Ads Marketplace Quality: builds auction and pricing optimization algorithms, supply optimization, and ad relevance solutions.
• Ads Creative Effectiveness: trains, adapts and fine-tunes LLMs/VLMs to help advertisers create images, videos and text; builds performance predictors and recommendation engines.

Role Description

Join the Ads organization as a Machine Learning Engineer and contribute to the full ML lifecycle — from research and modeling to deployment and production optimization. You will work on problems across ad ranking, bidding, measurement, and optimization and build scalable, reliable ML systems that deliver value to advertisers and users.

Responsibilities

• Design, build, and deploy industrial-scale ML models for ad ranking, bidding, and optimization.
• Own the full ML lifecycle: ideation, research, building scalable serving systems, and maintaining models in production.
• Perform systematic feature engineering to convert 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 implementing monitoring, alerting, and automated retraining pipelines.
• Research and adopt state-of-the-art ML techniques; contribute to team strategy and roadmap.

Required Qualifications

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

Pay Transparency & Benefits

• Base pay range (U.S.-based): $185,800 - $260,100 USD.
• In addition to base salary, eligibility for RSUs and possibly commission depending on position.
• U.S. benefits include medical, dental, vision, 401(k) with employer match, generous time off, and parental leave.

Interview & Privacy Notes

• In select roles/locations, interviews may be recorded, transcribed, and summarized by AI; candidates can opt out prior to interviews.
• Reddit will collect identifiers, professional/employment information, sensory information (audio/video), and other information candidates choose to share. Recordings are deleted promptly after hiring decisions.

Equal Opportunity

Reddit is an equal opportunity employer and provides reasonable accommodations for qualified individuals with disabilities and disabled veterans in the application process.