About the teamShopper Journey Services (SJS) is Zillow's engine for authenticated user intent and a core enabler of Home Details Page (HDP) experiences. We gather rich, explicit and implicit signals from authenticated shoppers and co‑shoppers, refine them into durable models, services, and display‑ready data, and activate those capabilities across Zillow's ecosystem to deliver personalized, high‑quality experiences. Our charter spans two tightly connected areas: User Intent & Applied AI, where we build the pipelines, services, and evaluation capabilities that turn user signals into intelligence and AI‑powered experiences, and the HDP Backend Platform, where we power HDP with robust, low‑latency, display‑ready data. AI is both a product capability and an engineering accelerator for this team, and we are investing in LLM‑ and ML‑powered workflows, evaluation, and agentic systems while modernizing our conventional backend stack.About the roleWe are looking for a P5 Principal Software Engineer, Applied AI Services to lead the architecture and evolution of our backend and AI systems across Shopper Journey Services and partner teams. In this cross‑cutting role, you will operate at the intersection of large‑scale backend systems (microservices, APIs, data stores, event‑driven architectures, ZGCP/Kubernetes, AWS‑class cloud infrastructure) and applied AI/ML systems (offline data ingestion, feature and signal pipelines, LLM/ML‑powered capabilities, evaluation frameworks, and AI‑driven workflows). You will play a leading role in how we bring AI capabilities into production services safely and repeatably, evolve our user intent flywheel and HDP backend platform, and define system‑wide standards, frameworks, and abstractions that enable many teams to ship AI‑powered features faster and with higher quality. This is a hands‑on principal IC role where you will both design and build systems yourself and provide technical leadership across multiple teams and orgs, without direct