Principal Software Engineer, Applied AI Services

Zillow Zillow · Consumer · Mexico City, Mexico

Principal Software Engineer to lead the architecture and evolution of backend and AI systems, focusing on integrating AI/ML/LLM capabilities into production services. The role involves building pipelines, services, and evaluation frameworks, and defining system-wide standards for AI-powered features.

What you'd actually do

  1. Architect end‑to‑end applied AI services that connect offline data ingestion, AI/ML/LLM workflows, and online services and APIs, defining shared patterns for batch and streaming data pipelines (e.g., Databricks, Spark, Kafka or equivalents), feature and signal stores, and evaluation and guardrail frameworks for AI‑powered capabilities.
  2. Create reusable building blocks—such as libraries, templates, and reference implementations—that make it straightforward for product teams to integrate AI into their services and ship AI‑powered features faster.
  3. Drive AI/ML and LLM‑powered systems from prototype to production, including ingestion and transformation of training and inference data, integration of models and LLMs into online decision flows and APIs, and the definition of evaluation methodologies, metrics, and regression gates (e.g., LLM‑as‑judge, offline/online evaluation, human‑in‑the‑loop review loops).
  4. Partner with AI/ML, Agentic AI, and data platform teams to clarify ownership boundaries and interfaces (for example, around cross‑cutting evaluation capabilities such as Evaluate MCP), and to ensure AI systems remain measurable, debuggable, and reproducible as they scale.
  5. Lead multi‑team technical initiatives that span SJS, AI/ML teams, HDP, and other backend groups, defining and rolling out system‑wide standards and abstractions for APIs and contracts (REST/GraphQL, events, DRDCs), data schemas and lineage across offline and online paths, and observability, evaluation, and operational runbooks for AI‑powered services.

Skills

Required

  • 10+ years of software engineering experience
  • delivering and scaling complex, distributed backend systems
  • large‑scale microservices
  • event‑driven architectures
  • cloud environments (AWS or equivalent)
  • Kubernetes
  • databases, caching, and data‑intensive services
  • schema design, performance optimization, and reliability
  • data pipelines and ML workflows (e.g., Databricks, Spark, Kafka, Airflow or equivalents)
  • system‑wide abstractions, frameworks, or platforms
  • building or scaling AI/ML or LLM‑powered systems in production
  • integrating models or LLMs into production services
  • owning or co‑owning data ingestion, feature pipelines, or model‑serving paths
  • defining or implementing evaluation and guardrail mechanisms
  • led cross‑team technical initiatives as an IC

Nice to have

  • AI/ML/LLM workflows
  • evaluation and guardrail frameworks
  • agentic systems
  • LLM‑as‑judge
  • offline/online evaluation
  • human‑in‑the‑loop review loops
  • Agentic AI
  • data platform teams
  • APIs and contracts (REST/GraphQL, events, DRDCs)
  • data schemas and lineage
  • observability
  • operational runbooks
  • background agents for KTLO
  • AI‑assisted design, implementation, and testing patterns

What the JD emphasized

  • lead the architecture and evolution of our backend and AI systems
  • operate at the intersection of large‑scale backend systems
  • applied AI/ML systems
  • build the pipelines, services, and evaluation capabilities
  • AI‑powered experiences
  • AI is both a product capability and an engineering accelerator
  • investing in LLM‑ and ML‑powered workflows, evaluation, and agentic systems
  • bring AI capabilities into production services safely and repeatably
  • evolve our user intent flywheel and HDP backend platform
  • define system‑wide standards, frameworks, and abstractions
  • enable many teams to ship AI‑powered features faster and with higher quality
  • hands‑on principal IC role
  • design and build systems yourself
  • provide technical leadership across multiple teams and orgs
  • architect end‑to‑end applied AI services
  • AI/ML/LLM workflows
  • evaluation and guardrail frameworks for AI‑powered capabilities
  • integrate AI into their services and ship AI‑powered features faster
  • Drive AI/ML and LLM‑powered systems from prototype to production
  • integration of models and LLMs into online decision flows and APIs
  • definition of evaluation methodologies, metrics, and regression gates
  • Partner with AI/ML, Agentic AI, and data platform teams
  • ensure AI systems remain measurable, debuggable, and reproducible
  • Lead multi‑team technical initiatives
  • system‑wide standards and abstractions
  • observability, evaluation, and operational runbooks for AI‑powered services
  • Mentor senior engineers
  • champion the use of AI as a force multiplier for engineering
  • background agents for KTLO
  • AI‑assisted design, implementation, and testing patterns
  • define which workflows should be agent‑assisted versus human‑led
  • built large‑scale microservices and event‑driven architectures
  • data pipelines and ML workflows
  • how they connect to online systems
  • designed system‑wide abstractions, frameworks, or platforms
  • building or scaling AI/ML or LLM‑powered systems in production
  • integrating models or LLMs into production services
  • owning or co‑owning data ingestion, feature pipelines, or model‑serving paths
  • defining or implementing evaluation and guardrail mechanisms
  • led cross‑team technical initiatives as an IC

Other signals

  • building pipelines and services for AI-powered experiences
  • integrating models and LLMs into production services
  • defining evaluation methodologies and guardrail frameworks
  • leading cross-team technical initiatives for AI systems