Research Engineer Intern

As a Research Engineer Intern at Mercor, you’ll work at the intersection of engineering and cutting-edge AI research. You’ll contribute directly to post-training and RLVR, data generation, and large-scale evaluation workflows. Your work will be used to train Large Language Models to master tool-use, agentic behavior, and real-world reasoning. You’ll shape rewards, experiment with algorithmic improvements (GRPO, DAPO, etc.), and enhance data quality to improve model performance in real production environments. You’ll help design and evaluate datasets, create scalable data augmentation pipelines, and build rubrics that push the boundaries of what LLMs can learn.