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xAIxAIPalo Alto, CA

Member of Technical Staff - Post-Training and RL

Develops advanced post-training and reinforcement learning techniques like RLHF/DPO and reward modeling to enhance AI model reasoning, truthfulness, and real-world capabilities at xAI. Seeks passionate AI enthusiasts obsessed with truth-seeking models; prior experience preferred but not required.

180k – 600k
On-siteML Engineering

About the role

Responsibilities

  • Work on critical post-training and reinforcement learning challenges, including reward modeling, preference optimization (RLHF/DPO), and RL for improving reasoning, truthfulness, and real-world capabilities.

Basic Qualifications

  • Believe truth-seeking AI is the most important and challenging problem.
  • Obsessed about building incredibly useful models through post-training and RL techniques.
  • Power user of AI models and eager to push boundaries with reinforcement learning and alignment methods.
  • Previous work on post-training, RLHF, or models used by millions is a big plus (relevant experience not required).
  • Take pride in work and thrive in meritocratic environments.

Compensation and Benefits

  • $180,000 - $600,000 USD
  • Equity, comprehensive medical, vision, and dental coverage
  • Access to 401(k) retirement plan
  • Short & long-term disability insurance
  • Life insurance
  • Various other discounts and perks

Skills

Reinforcement LearningRLHFDpoReward ModelingAi AlignmentPost-TrainingPyTorchJAXTransformersMachine Learning

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