# Machine Learning Systems Research Engineer, Agent Post-training - Enterprise GenAI

**Company:** [Scale AI](https://hotfix.jobs/companies/scale-ai)
**Location:** San Francisco, CA, New York, NY, Seattle, WA
**Role:** AI Research
**Salary:** $218k – $273k/yr
**Experience:** 1+ years
**Skills:** PyTorch, CUDA, Transformers, Flash Attention, RLHF, Rlvr, Ppo, Grpo, Gpu Cluster, Multi-Node Training
**Posted:** 2026-02-12

> Develops and optimizes post-training algorithms for agent RL platforms, focusing on LLM training, inference frameworks, and multi-agent systems. Requires 1-3 years production LLM experience, expertise in PyTorch/CUDA, RLHF/PPO, and advanced degree.

## Job Description

## Responsibilities

- Build, profile and optimize our training and inference framework.
- Post-train state of the art models, developed both internally and from the community, to define stable post-training recipes for our enterprise engagements.
- Collaborate with ML teams to accelerate their research and development, and enable them to develop the next generation of models and data curation.
- Create a next-gen agent training algorithm for multi-agent/multi-tool rollouts.

## Requirements

- At least 1-3 years of LLM training in a production environment
- Passionate about system optimization
- Experience with post-training methods like **RLHF/RLVR** and related algorithms like **PPO/GRPO** etc.
- Ability to demonstrate know-how on how to operate the architecture of the modern **GPU cluster**
- Experience with multi-node LLM training and inference
- Strong software engineering skills, proficient in frameworks and tools such as **CUDA**, **PyTorch**, **transformers**, **flash attention**, etc.
- Strong written and verbal communication skills to operate in a cross functional team environment.
- **PhD** or **Masters** in Computer Science or a related field

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