A focused team building infrastructure and methods that make open models systematically better after initial training.

Member of Technical Staff — Post-Training Research

San FranciscoOn-site$200K - $350K2 - 6 yearsReferral bonus eligible
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In your first year, you will design and run experiments that meaningfully shift the behavior of large language models — improving reasoning depth, instruction fidelity, and safe refusal boundaries. You will own end-to-end research loops: forming hypotheses about where post-training falls short, scripting large-scale evaluations in PyTorch, and shipping improvements that compound across model versions. This is not a lab notebook role; your work will land directly in production fine-tuning pipelines that serve real downstream users. The team is small enough that your fingerprints will be unmistakable, and the research agenda is still being shaped.

What they're looking for

  • 2–6 years of hands-on experience training or fine-tuning large neural networks, with deep fluency in Python and PyTorch
  • Track record of empirical research in areas such as RLHF, DPO, constitutional AI, red-teaming, or related alignment and post-training techniques
  • Comfort designing rigorous experiments at scale: building data pipelines, instrumenting metrics, and making tradeoffs between cost, latency, and model quality
  • Strong communication instincts — you can defend experimental design choices and distill failure modes into clear next steps without relying on jargon
  • Bias toward action in an environment where priorities shift with fresh experimental evidence; you would rather run the small pilot tonight than over-plan for a perfect run next week

Tech stack

PythonPyTorch

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