Principal Machine Learning Engineer (Memory & Context)
First seen by Alion on Oct 20, 2026. Zillow scores A on the Alion truth index.
About the team
The Agentic AI team at Zillow is at the forefront of transforming the real estate industry by helping millions of people use AI assistants to find their next home. We aim to redefine the home shopping and transaction experience by providing an always-on assistant that integrates personalized user insights with Zillow's knowledge. Within this organization, our team owns how the assistant remembers and understands each user across a home search that can last for months: agent memory, context engineering, and the evaluation of agents running in production. We are a senior, fast-moving team of machine learning engineers who do the science and own taking it to production.About the role
As a Principal Machine Learning Engineer on the Agentic AI team, you will get to:
- Own the architecture of agent memory: what Zillow's assistant remembers about each user across conversations, and how memories are written, retrieved, updated, and retired
- Lead context engineering for production agents: assembling, prioritizing, and compressing context from conversation history, user memory, tools, and skills so every response is relevant, fast, and cost-efficient
- Build and orchestrate agents end to end, from prompt and context design to deployment and operation in production
- Define evaluation frameworks for memory and context quality, offline and online, and use them to drive product and technical decisions
- Stay on the cutting edge of emerging agentic paradigms, including memory architectures and long-context techniques, and convert them into tangible product innovation
- Lead complex, multi-team initiatives and communicate technical direction clearly to engineers, partner teams, and leadership
Who you are
You are a hands-on technical leader with high agency: when a problem is ambiguous or blocked, you go talk to the people who can solve it, and you make your work visible.
Must-haves
- A master's degree or above, or equivalent experience, in Computer Science, Electrical Engineering, or a related field
- 5+ years of experience deploying large-scale ML systems, including at least the most recent year building and shipping LLM-based agents in production
- Hands-on experience building agents end to end: orchestration, prompt engineering and optimization, and context engineering
- Experience evaluating agentic systems and using those results to improve them
- Proven technical leadership: you have influenced technical direction across teams and mentored other engineers
- Strong communication skills, including presenting to senior leadership
- Strong programming skills in Python and familiarity with agentic AI frameworks such as LangGraph, Agents SDK, or AutoGen
Nice-to-haves
- Experience designing agent or user memory systems (long-term, episodic, or user-profile memory)
- Experience with dialogue systems that sustain long, multi-session conversations
- Personalization of AI assistants from conversation history
- Publications, patents, or open-source contributions related to memory, long-context models, or agents
Get to know us
At Zillow, we’re reimagining how people move-through the real estate market and through their careers. As the most-visited real estate platform in the U.S., we help people navigate buying, selling, financing and renting with greater ease and confidence. Whether you're working in tech, sales, operations, or design, you’ll be part of a company reshaping an industry and helping more people make home a reality.
How we work is a key part of that transformation. Through Cloud HQ, our strategic approach to distributed work, most employees have the flexibility to work from wherever they’re most productive-enabling us to move fast, stay connected and deliver on our people promise.
Zillow is honored to be recognized among the best workplaces in the U.S. Zillow was named one of FORTUNE 100 Best Companies to Work For® in 2026, and included on TIME’s America’s Best Companies 2026 list, reflecting our commitment to creating an innovative, inclusive, and engaging culture where employees are empowered to grow.
No matter where you sit in the organization, your work will help drive innovation, support our customers, and move the industry-and your career-forward, together.
Zillow Group is an equal opportunity employer committed to fostering an inclusive, innovative environment with the best employees. We are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity or Veteran status. If you have a disability or special need that requires accommodation, please contact your recruiter directly.
Qualified applicants with arrest or conviction records will be considered for employment in accordance with applicable state and local law.
Los Angeles County applicants: Job duties for this position include: work safely and cooperatively with other employees, supervisors, and staff; adhere to standards of excellence despite stressful conditions; communicate effectively and respectfully with employees, supervisors, and staff to ensure exceptional customer service; and follow all federal, state, and local laws and Company policies. Criminal history may have a direct, adverse, and negative relationship with some of the material job duties of this position. These include the duties and responsibilities listed above, as well as the abilities to adhere to company policies, exercise sound judgment, effectively manage stress and work safely and respectfully with others, exhibit trustworthiness and professionalism, and safeguard business operations and the Company’s reputation. Pursuant to the Los Angeles County Fair Chance Ordinance, we will consider for employment qualified applicants with arrest and conviction records.