About the role Our client is a well-funded AI startup building production-grade ML infrastructure used by enterprise customers. They are looking for a Senior AI/ML Engineer to own model training pipelines, evaluation systems, and inference serving at scale. Full-time, on-site in San Francisco. What you will do • Design and ship end-to-end ML systems: data pipelines, training, evaluation, deployment • Own model performance, latency, and cost trade-offs in production • Build evaluation harnesses and offline benchmarks for fast iteration • Work directly with product to translate ambiguous goals into measurable model improvements • Mentor other engineers on ML best practices and code quality What we are looking for • 4+ years of applied ML engineering in production environments • Hands-on experience with LLMs, fine-tuning, RAG, or large-scale recommender systems • Strong Python and PyTorch (or JAX) fundamentals • Experience with distributed training, GPU optimization, or inference serving • Pragmatic about trade-offs between research-grade and ship-grade work This role is presented by a recruiting partner. Company name shared after an initial conversation.