Staff Machine Learning Engineer, App Ads Modeling

<div class="content-intro"><div class="c-message_kit__blocks c-message_kit__blocks--rich_text"> <div class="c-message__message_blocks c-message__message_blocks--rich_text" data-qa="message-text"> <div class="p-block_kit_renderer" data-qa="block-kit-renderer"> <div class="p-block_kit_renderer__block_wrapper p-block_kit_renderer__block_wrapper--first"> <div class="p-rich_text_block"> <div class="p-rich_text_section">Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 130 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit <a class="c-link" href="http://www.redditinc.com/" target="_blank" data-stringify-link="http://redditinc.com" data-sk="tooltip_parent">www.redditinc.com</a>.</div> </div> </div> </div> </div> </div></div><p><strong>Reddit has a flexible first workforce!</strong></p> <p>We’re looking for a Staff-level 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.</p> <p>The ideal candidate will bring strong end-to-end modeling expertise, a deep understanding of modern deep learning techniques, and a passion for building systems that drive measurable impact in ads marketplaces. While ads experience is a plus, strong modelers from recommendation systems, search relevance, or other performance-driven domains are encouraged to apply.&nbsp;This position will sit on the App Ads Modeling team and report directly into the Ranking Org.</p> <p><strong>Responsibilities:</strong></p> <ul> <li>Design and train advanced ML models (e.g., DNNs, transformers) to power Reddit Ads Ranking</li> <li>Develop and optimize features including embeddings, contextual signals, and cross-session behavior</li> <li>Work closely with product, infra, and data teams to drive end-to-end model deployment and performance analysis</li> <li>Mentor other MLEs and contribute to modeling best practices across the org</li> <li>Shape the long-term modeling vision across one or more domains (conversion, app ads, shopping, brand, etc.)</li> </ul> <p><strong>Required Qualifications:</strong></p> <ul> <li>7+ years of industry experience, including several years in appl