Senior Applied Scientist - Agentic AI & Reward Modeling

Zillow Group; United States; Remote; USD 170,000 - 260,000; Full time

Job summary

Zillow Group is seeking a Senior Applied Scientist to lead model post-training and reward modeling efforts within the Agentic Foundations team. You will own end-to-end LLM post-training pipelines, design reward models, and drive online/offline evaluations, collaborating across product, engineering, science, platform, and data teams to translate advances into production impact.

You will mentor scientists and MLEs, work with PyTorch/TensorFlow on GPU infrastructure, and contribute to

Qualifications

• Master's degree or higher in Computer Science or a related field.
• Hands-on experience with LLM post-training and RL fine-tuning: SFT, DPO, RFT/GRPO, running end-to-end training runs on GPU infrastructure.
• Exposure to reward model development — research-level experience is sufficient; production deployment is not required.
• Strong knowledge of generative AI, including foundation models, transformers, reinforcement learning, and preference learning.
• Ability to independently scope and solve ambiguous problems end-to-end while providing technical leadership to scientists and MLEs.

Responsibilities

• Own LLM post-training pipelines — SFT, DPO, and reinforcement fine-tuning (RFT/GRPO) — running training end-to-end on GPU infrastructure.
• Build and train fast, multi-category reward models (PRMs) that emit scalar signals from contrastive preference pairs.
• Design on-policy and online assessment: score live agent trajectories using LLM-as-a-Judge frameworks.
• Translate offline evaluation rubrics into generalizable reward functions that work on arbitrary production traces.
• Independently drive complex work end-to-end by collaborating across partner teams.
• Provide technical leadership and mentorship while helping translate state-of-the-art AI research into production impact.

Skills

Python

LLM post-training

RL fine-tuning

Reward modeling

Ambiguity solving

Education

Master's degree in Computer Science or related field

PhD (nice-to-have)

Tools

PyTorch

TensorFlow

GPU infrastructure

Job description

Zillow Group is seeking a Senior Applied Scientist to lead model post-training and reward modeling efforts within the Agentic Foundations team. You will own end-to-end LLM post-training pipelines, design reward models, and drive online/offline evaluations, collaborating across product, engineering, science, platform, and data teams to translate advances into production impact.

You will mentor scientists and MLEs, work with PyTorch/TensorFlow on GPU infrastructure, and contribute to