Machine Learning Engineer

About The CompanyReddit is a vibrant community of communities, built on shared interests, passion, and trust. It is renowned for fostering the most open and authentic conversations on the internet. With over 100,000 active communities and approximately 101 million daily active unique visitors, Reddit stands as one of the largest sources of information on the web. The platform enables users to submit, vote, and comment on topics they care about, creating a dynamic environment for engagement and knowledge sharing.About The RoleReddit is seeking a highly skilled and innovative Ads Targeting Machine Learning Engineer to join the Ads Targeting Quality team. In this role, you will be instrumental in designing, developing, and deploying ML systems that enhance targeting products, ultimately delivering highly relevant audiences to advertisers under appropriate contexts. Your work will involve building large-scale offline and online retrieval systems to improve contextual and behavioral targeting. As a key member of the team, you will own the end-to-end development of ML-based targeting solutions such as auto targeting and user lookalikes, driving research, experimentation, and implementation of advanced models including deep learning architectures like GNNs, transformers, and LLMs. You will collaborate with cross-functional teams, including product managers, engineers, and researchers, to align technical strategies with business goals and ensure the successful deployment of scalable, impactful solutions. Mentoring junior team members and leading complex projects will be essential components of this role, contributing to Reddit’s mission of delivering a best-in-class advertising experience.QualificationsTech lead experience in a product-focused machine learning team, guiding research and technical strategy to improve business outcomesProven experience with ads retrieval modeling, ranking, or recommendation systemsExpertise in deep learning models for retrieval, including two-tower architectures, GNNs, transformers, and LLMsMinimum of 5 years of end-to-end experience in training, evaluating, testing, and deploying machine learning modelsAt least 2 years of hands-on experience with TensorFlow or PyTorchExperience with large-scale data processing and pipeline orchestration tools such as Spark, Dataflow, Kubeflow, Airflow, or BigQueryKnowledge of nearest-neighbor search systems is a significant plusExperience working with cross-functional stakeholders across research, product, and infrastructure teamsBackground in deep learning, representation learning, or transfer learning is preferredPrior experience leading ML initiatives within a product team is highly desirableResponsibilitiesOwn the complete lifecycle of ML-based targeting products, including design, development, testing, and deploymentDefine and execute the research roadmap for complex retrieval models, leveraging advanced deep learning techniquesLead day-to-day project management, ensuring timely delivery and alignment with strategic goalsCollaborate with product managers and cross-functional teams to develop and prioritize project roadmaps based on data analysis and industry trendsResearch, implement, and evaluate new model architectures to optimize targeting accuracy and advertiser outcomesProvide mentorship and technical guidance to junior machine learning engineersDesign and conduct offline and online experiments to validate model performance and iterate improvementsWork with large-scale data systems and ensure seamless integration of ML solutions into production environmentsEngage with stakeholders across research, engineering, and marketing to align on project goals and deliver impactful solutionsBenefitsComprehensive healthcare benefits and income replacement programs401(k) matching contributionsFamily planning support and gender-affirming careMental health and coaching resourcesFlexible vacation policies and Reddit Global Days offGenerous paid parental leavePaid volunteer time offEqual OpportunityReddit is proud to be an equal opportunity employer. We are committed to building a diverse workforce that reflects the communities we serve. We provide reasonable accommodations for qualified individuals with disabilities and disabled veterans throughout the application and interview process. If you require an accommodation due to a disability, please inform your recruiter. We welcome applicants from all backgrounds and are dedicated to fostering an inclusive environment where everyone can thrive.