Senior Machine Learning Engineer, Ads Engagement Modeling

As a company, Reddit primarily generates revenue through advertising, and we're working towards building a massive business to fund our mission. We distinguish ourselves from other digital ad platforms by attracting advertisers who want to connect with a specific target audience because of our passionate and engaged communities.

The Ads Engagement Modeling team is responsible for predicting ads engagement rates used in auctions for upper and middle funnel ad products. The team focuses on Click-Through Rate (CTR) prediction to optimize ad engagement and marketplace efficiency, particularly for Reddit’s most critical ad product: CPC (Cost-Per-Click). Additionally, the team manages video view modeling, landing page optimization, and pCTR (predicted CTR) models for product ads.

The Engagement Modeling team collaborates closely with both upstream and downstream teams to drive the development of new features and model iterations, continually improving ranking models for upper and middle funnel products.

Project highlights:

• Model Architecture Engineering: Explore and implement state-of-the-art architectures such as multi-task learning and calibration models.
• Systematic Feature Engineering: Develop powerful features from Reddit’s data using techniques like aggregation, embedding, sub-models, and content understanding.
• Zero-to-One Model Development: Build models from scratch, collaborating with cross-functional teams on Go-To-Market strategies for vertical products like video view models, landing page optimization, and product ads.

As a Senior Machine Learning Engineer on the Engagement Modeling team, you will be responsible for researching, formulating, and executing projects, while actively contributing to the end-to-end implementation process. You will work closely with cross-functional teams to ensure the successful delivery of products. This role also offers the opportunity to leverage your expertise and help shape the future of ads ML at Reddit.

Your Responsibilities:

• Build industry-level models for critical machine learning tasks, applying advanced modeling techniques.
• Research, implement, test, and launch innovative model architectures, including deep neural networks with advanced pooling and feature interaction designs.
• Conduct systematic feature engineering to transform diverse raw data from Reddit (dense, sparse, behavioral, content, etc.) into actionable features using techniques such as aggregation, embedding, sub-models, and more.
• Serve as a mentor and advocate across teams, fostering collaboration and knowledge sharing.
• Contribute meaningfully to the team’s strategic direction. We value everyone’s input and encourage active participation in shaping our future roadmap.

Who You Might Be:

• Proven track record of driving KPI improvements through strategic work in model architecture and feature engineering.
• 4+ years of experience building industry-level deep learning models.
• 4+ years of experience with mainstream ML frameworks, such as TensorFlow and PyTorch.
• 4+ years of hands-on experience with the full lifecycle of training, evaluating, testing, and deploying industry-level models.
• Experience iterating large-scale neural network models in a production environment is a must.
• Familiarity with the Ads domain is a strong plus.

We're committed to hiring the best talent and building a diverse team. We're proud to be completely remote-friendly and will continue to offer remote work options beyond the pandemic.

Join us at Reddit, and help us build a community that is inclusive and empowering for everyone.

Benefits:

• Comprehensive Healthcare Benefits
• 401k Match
• Family Planning Support
• Gender-Affirming Care
• Mental Health Coaching Benefits
• Flexible Vacation Reddit Global Days off
• Generous paid Parental Leave
• Paid Volunteer time off