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Software Engineer, RL Data

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San Francisco · Full-time · Onsite · Posted Oct 12, 2026

At a glance

Employment
Full-time
Workplace
Onsite
Location
San Francisco

About the role

  • On the RL Data team, you decide what data is used for our agents, including which problems they practice and how they are judged.
  • You take weaknesses and turn them into training data to fix them, then show the next model is measurably better.
  • You form hypotheses about why data is helping or misleading the model, build the systems to test them, run ablations, and read rollouts.

Responsibilities

  • Turning a capability gap into thousands of verifiable tasks
  • Building environments that behave like production
  • Designing graders for open-ended work that separate good solutions from bad
  • Building automated checks that catch reward hacking, leaked answers, broken environments, and invalid paths before data reaches training
  • Scaling from a thousand hand-checked tasks to millions with filters and trusted judges

Requirements

  • Strong software engineering fundamentals
  • Built non-trivial systems in Python such as data pipelines, test or eval infrastructure, sandboxes, or backend services
  • Taste for what makes an environment trustworthy
  • Careful and systematic approach to understanding aggregate metrics and close reading of raw outputs
  • Enjoyment of turning messy, open-ended problems into repeatable, high-quality data production systems

Preferred qualifications

  • RL or ML experience is a plus but not required

Skills

  • Python

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Software Engineer, RL Data

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