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Research Engineer, Reinforcement Learning

Develops RL environments and fine-tunes language models using PPO, DPO, and KTO to enhance agentic capabilities for data infrastructure tasks. Requires deep RL expertise, LLM fine-tuning knowledge, and strong problem-solving skills.

San Francisco, CAML EngineeringHybrid

About the role

Responsibilities

  • Develop and refine reward functions to optimize agent behavior for complex data engineering tasks.
  • Create RL gym environments for language model agents.
  • Fine-tune language models using reinforcement learning techniques such as PPO, DPO, and KTO.
  • Stay at the forefront of research on RL for language models, incorporating advancements like GRPO, SWE-Gym, and SWE-RL into practical applications.
  • Curate and build high-quality datasets for supervised fine-tuning (SFT) and RLHF.
  • Design experiments to evaluate and improve the agentic capabilities of language models in data environments.

Requirements

  • Deep understanding of reinforcement learning, reward shaping, and optimization strategies.
  • Strong familiarity with LLM fine-tuning techniques (PPO, DPO, KTO) and their applications in reinforcement learning.
  • Knowledge of recent advancements in RL for language models (GRPO, SWE-Gym, SWE-RL).
  • Experience curating and constructing high-quality datasets for fine-tuning.
  • Strong problem-solving skills and a history of working on complex ML projects.
  • High agency—ability to work independently, experiment proactively, and drive research initiatives forward.

Nice-to-Haves

  • Experience with distributed training in PyTorch (DDP, FSDP).
  • Hands-on experience designing RL environments for traditional RL problems.
  • Contributions to open-source projects in RL, LLMs, or ML infrastructure.
  • Familiarity with data lakes and warehouses (Snowflake, BigQuery, Redshift).

Benefits

  • 100% employer-covered health, dental, and vision insurance.
  • 401(k) with company match.
  • Access to Bay Club or Equinox in San Francisco.

Skills

Reinforcement LearningPpoDpoKtoRLHFPyTorchGymGrpoSwe-GymSwe-Rl

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