Research Engineer

AI/Research Engineer

San Francisco, CA - 5 days onsite $180K-$240K + early-stage equity

My client is an early-stage AI research company building advanced reasoning systems and post-training infrastructure for enterprise AI applications. The team comes from leading AI labs and startups, with backgrounds spanning LLMs, reinforcement learning, distributed systems, and applied research.

They're looking for a highly technical Research Engineer to work on:

• LLM post-training and fine-tuning
• RLHF / DPO / reward modeling
• Synthetic data generation
• Evaluation frameworks and reasoning systems
• Distributed training and inference infrastructure
• Agentic AI workflows and production deployments

The role is highly hands-on and suited to someone who has actually trained, evaluated, and deployed models - not just built on top of APIs.

Requirements:

• Strong Python + PyTorch experience
• Hands-on LLM training and fine-tuning experience
• Strong ML/AI fundamentals
• Experience working in fast-moving technical environments
• Strong engineering ability paired with a research mindset

Nice to have:

• RLHF / evals / synthetic data experience
• Distributed systems exposure
• Publications or open-source contributions
• Experience at strong AI startups or research labs