Staff Research Engineer, Post-training & Evaluation

Reddit is continuing to grow our teams with the best talent. This role is completely remote friendly within the United States. If you happen to live close to one of our physical office locations (San Francisco, Los Angeles, New York City & Chicago) our doors are open for you to come into the office as often as you'd like.

The AI Engineering team at Reddit is building our own Reddit-native foundational Large Language Models (LLMs). This team sits at the intersection of applied research and massive-scale infrastructure, training models that truly understand the unique culture, language, and structure of Reddit communities. You'll join a team of distinguished engineers and researchers building the "engine room" of Reddit's AI future — the foundational models that power Safety & Moderation, Search, Ads, and the next generation of consumer products.

As a Staff Research Engineer for Post-Training & Evaluation Science, you will own the science of our model development "feedback loop." While pre-training builds the base models, you define how we measure whether those models are safe, smart, and "Reddit-native," and you set the post-training methodology that turns base checkpoints into high-performing endpoints. You will define the Reddit Benchmark — our internal standard for rigorous model quality across both generation and representation — and own the evaluation science that the rest of the org's iteration depends on.