Research Engineer / Scientist, Reinforcement Learning

32 minutes agoSalary: 230K - 450KLondon, UKRemoteFull TimeAiJobs by Harvey

Harvey is an AI platform for legal and professional-services organizations.

Series F+Recently funded
Distributed
About Harvey

Harvey provides agents and collaborative tools for legal work, including legal research, document analysis, secure workspaces, contract intelligence, and organization-level analytics.

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Skills

Candidate Availability

Required and preferred rules are kept separate and reflect the wording in the original posting.

About the Role

You will own how Harvey adapts and improves open-weight models for legal work. You'll design and run SFT and RL post-training experiments, develop rewards and verifiers for semi-verifiable tasks, debug large-scale training, and carry ideas through to models used by customers.

Requirements

  • Hands-on experience post-training LLMs with SFT and RL including preference optimization
  • Deep ML fundamentals and experience with distributed training runs
  • Strong Python engineering skills
  • Research experience in RL for language models or reward modeling

Responsibilities

  • Own a research agenda to improve long-horizon legal reasoning and agentic workflows
  • Design and run post-training experiments across SFT and RL
  • Develop reward functions and verifiers for semi-verifiable tasks
  • Run and debug training at scale, addressing divergence, reward hacking and instability
  • Build rigorous evals to track improvements and decide what ships
  • Design, implement, test and debug code across the research stack

Benefits

  • Equity
Research Engineer / Scientist, Reinforcement Learning at Harvey | JobStash