We’re looking for a Staff Machine Learning Engineer to join Reddit’s Ads Ranking Org! This role is part of a broader effort to enhance Reddit’s ML-powered ad ranking systems through improved model architectures, contextual embeddings, and conversion-optimized modeling. This position allows the opportunity to contribute across key modeling focus areas such as conversion, app ads, shopping, brand ads, or core ranking.

What you bring:

• 7+ years of industry experience, including several years in applied ML roles
• Deep experience with DNN architectures and ML frameworks (TensorFlow, PyTorch)
• Strong background in recommendation systems, ads ranking, or similar domains
• Experience working with large-scale datasets and complex feature pipelines
• Strong problem-solving and experimentation skills

Day-to-Day Responsibilities:

• Design and train advanced ML models (e.g., DNNs, transformers) to power Reddit Ads Ranking
• Develop and optimize features including embeddings, contextual signals, and cross-session behavior
• Work closely with product, infra, and data teams to drive end-to-end model deployment and performance analysis
• Mentor other MLEs and contribute to modeling best practices across the org
• Shape the long-term modeling vision across one or more domains (conversion, app ads, shopping, brand, etc.)

Most Challenging Aspects:

• Balancing generalization and specificity in modeling across different ad formats
• Managing trade-offs between model complexity, latency, and prediction quality
• Navigating cross-functional alignment to scale high-impact ML initiatives

What Differentiates This Role:

• Direct path to measurable product and revenue impact
• Opportunity to shape foundational ML modeling across Reddit Ads
• Flexible scope based on modeling strengths (conversion, app ads, core ranking, etc.)
• Exposure to diverse ad surfaces (feed, video, shopping, brand) and cutting-edge ML techniques

What We Offer:

• A dynamic, supportive work environment with a diverse team of engineers and cross-functional partners
• Opportunities for professional growth and development, with a focus on continuous learning and skill-building
• A competitive salary and benefits package, with a focus on work-life balance and employee well-being
• Flexible work arrangements, including remote work options, to support your individual needs and preferences
• The chance to work on high-impact projects that drive real results for our users and advertisers

Benefits:

• Comprehensive Healthcare Benefits and Income Replacement Programs
• 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

#LI-Remote

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