Staff Machine Learning Engineer, Ads Content Understanding

Staff Machine Learning Engineer for Ads Content Understanding (ACU). Lead the Commercial Content Understanding roadmap and act as technical owner for ACU’s signals and ML systems, splitting time roughly 50% in technical leadership/mentorship and 50% in hands-on modeling, pipelines, and debugging production systems. Responsibilities include providing technical leadership and mentorship to MLEs and SWE s, developing evaluation and quality monitoring systems for content understanding signals, driving operational excellence with SLOs, alerts, and dashboards, building and evolving content understanding capabilities for commercial conversations (e.g., reviews vs. recommendations vs. sentiment/stance; product entities and categories), designing and implementing signals pipelines and an ACU signals registry, collaborating with platform teams for scalable serving at Reddit’s scale, and guiding modern ML best practices (prompting, finetuning, distillation) and at least one major distillation effort. Oversee the full ML lifecycle (problem framing, data, modeling, evaluation, deployment, monitoring, oncall) with an emphasis on responsible AI (bias, safety, explainability). Benefits and salary range provided; this is a remote-US role (LI-Remote).