Machine Learning Systems Research Engineer, Agent Post-training - Enterprise GenAI

Scale AI is a leading AI data foundry focused on accelerating the development of AI applications. The ML Sys Research Engineer will work on building algorithms for the next-gen Agent RL training platform and support large-scale training while integrating state-of-the-art technologies to optimize the ML system. Responsibilities Build, profile and optimize our training and inference framework Post-train state of the art models, developed both internally and from the community, to define stable post-training recipes for our enterprise engagements Collaborate with ML teams to accelerate their research and development, and enable them to develop the next generation of models and data curation Create a next-gen agent training algorithm for multi-agent/multi-tool rollouts Skills At least 1-3 years of LLM training in a production environment Passionate about system optimization Experience with post-training methods like RLHF/RLVR and related algorithms like PPO/GRPO etc Ability to demonstrate know-how on how to operate the architecture of the modern GPU cluster Experience with multi-node LLM training and inference Strong software engineering skills, proficient in frameworks and tools such as CUDA, Pytorch, transformers, flash attention, etc Strong written and verbal communication skills to operate in a cross functional team environment PhD or Masters in Computer Science or a related field Benefits Comprehensive health, dental and vision coverage Retirement benefits A learning and development stipend Generous PTO A commuter stipend Company Overview Scale’s mission is to develop reliable AI systems for the world’s most important decisions. It was founded in 2016, and is headquartered in San Francisco, California, USA, with a workforce of 501-1000 employees. Its website is Company H1B Sponsorship Scale AI has a track record of offering H1B sponsorships, with 82 in 2025, 54 in 2024, 29 in 2023, 17 in 2022, 10 in 2021, 10 in 2020. Please note that this does not guarantee sponsorship for this specific role.