Mercor is organizing human intelligence to power the AI economy. We are powering frontier research, AI benchmarks, and AI agent training at scale for the top AI labs and enterprises. Backed by General Catalyst and Menlo.
About the role
As a Research Engineer at Mercor, you’ll work at the intersection of engineering and applied AI research. You’ll own benchmarking pipelines, evaluation systems, and failure analysis workflows that directly inform how we train and improve frontier language models. Your work will define how we measure tool use, agentic behavior, and real-world reasoning. You’ll design and run evals, build rubrics and scorers, and turn failure analysis into actionable improvements for post-training, RLVR, and data pipelines.
What they're looking for
- Strong applied research background, with focus on model evaluation, benchmarking, and/or failure analysis
- Strong coding skills and hands-on experience with ML models and evaluation code
- Solid grasp of data structures, algorithms, and backend systems
- Comfort with APIs, SQL/NoSQL, and cloud platforms for running and storing eval results
- Ability to reason about model behavior, experimental results, and data quality from evals and failure analyses
- Excitement to work in person in San Francisco five days a week in a high-intensity, high-ownership environment
More about this role
Mercor's mission is to organize human intelligence to power the AI economy. We're a leading AI data company, building the layer between human expertise and frontier models. Millions of domain experts on the platform are paid over $4 million per day to train frontier AI models. Mercor's APEX benchmark family measures AI's real-world impact on professional work. Mercor Enterprise brings this same infrastructure to Fortune 500 companies: helping companies capture how their best people actually work, translating that expertise directly back into agents.
Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society. Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our San Francisco, NYC, or London offices.
As a Research Engineer at Mercor, you’ll work at the intersection of engineering and applied AI research. You’ll own benchmarking pipelines, evaluation systems, and failure analysis workflows that directly...
Browse similar: Startup jobs · San Francisco Bay Area