Amazon Selection and Catalog Systems (ASCS) builds the systems that host and run the world's largest e-commerce product catalog. Within this organization, the Starfish Studio Model Services (SSMS) team is redefining prompt experimentation, metadata refinement, and LLM evaluation to improve Amazon product catalog data quality, automation, and workflow efficiency. We focus on reinforcement learning, automation, and AI-driven experimentation to build a unified hub for optimizing prompt generation and catalog enrichment at scale. As a Software Development Engineer (SDE) in SSMS, you will develop distributed systems powered by LLMs and multi-modal ML models to enhance prompt experimentation, metadata refinement, and catalog enrichment. Build GenAI-driven solutions that improves prompt quality and automation. Design AI-driven workflows for both structured/unstructured data to enhance prompt engineering and LLM evaluation. Partner with scientists and AI experts to integrate cutting-edge advancements in Generative AI, LLM, reinforcement learning, and automation. Develop systems that reduce operational friction and streamline workflow integrations for prompt testing, metadata refinement, and reinforcement learning-based improvements.