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Staff Machine Learning Engineer, Agent Eval Platform

Mountain View, CALIFORNIA, us💼 Full-time🗓 2026-08-26 → 2026-09-26

Core

Building the judgement layer of an agent evaluation platform to score multi-step agent trajectories in enterprise systems, creating calibrated signals for training and evaluation.

Role type

Staff Machine Learning Engineer (Agent Evaluation & Reward Modeling)

Builds

A calibrated judge system (rubrics, validators, LLM judges) and a process reward model for agentic AI.

Domain

Agentic AI, Enterprise Automation, LLM Evaluation

Deliverable

production ML models

Required skills

Applied ML fundamentals, Python, LLM evaluation and fine-tuning, rubric design, human-in-the-loop calibration, reward modeling, offline/online divergence analysis

Preferred skills

LLM-as-judge design, human annotation program management, search ranking/recsys evaluation, SFT/preference tuning, RLHF/RLAIF, agent trajectory analysis, prompt engineering as an engineering discipline

Technologies

Python, LLMs, SFT, RLHF, RLAIF

Responsibilities

Design shared base judges with per-item rubrics; split validation between deterministic validators and LLM judges; implement confidence-based scoring routing; run calibration loops against human labels; fine-tune small judge models; analyze offline/online divergence; build process reward models for agent optimization.

Seniority

Staff, hands-on IC with strategic ownership

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