Principal Engineer, Shopping & Delivery Infra

Role overview

The Principal Engineer sets the long-term technical direction for indexing and retrieval infrastructure that powers core discovery, ads, and shopping experiences. The role sits at the intersection of platform engineering, machine learning, and product, shaping how fresh, relevant, and cost-efficient candidates are generated at massive scale. It is a senior, hands-on technical leadership position focused on architectural modernization, cross-org alignment, and engineering excellence.

Responsibilities

- Define and drive the multi-year technical vision for indexing and retrieval infrastructure across core, ads, and shopping surfaces - Lead cross-organization initiatives to modernize indexing architecture, including unified real-time and incremental retrieval systems - Partner with engineering, product, ML, and infrastructure leaders to align priorities, resolve tradeoffs, and deliver shared platform capabilities - Guide system design, architecture reviews, and execution on platform changes spanning document ingestion, indexing, retrieval, and quality evaluation - Build shared platform capabilities such as common metrics, tuning surfaces, and debugging workflows to improve relevance, safety, and cost tradeoffs - Mentor senior engineers and technical leaders, raising the bar for engineering judgment, collaboration, and operational excellence - Use AI-assisted tooling to accelerate analysis, prototyping, design drafting, and synthesis of platform insights, with strong attention to correctness and reliability

Requirements

- Deep expertise building and evolving large-scale indexing, search, recommendation, or ads retrieval systems, including real-time and incremental architectures - Strong technical leadership experience operating across multiple teams or organizations, influencing direction and driving complex platform decisions - Proven track record leading large modernization efforts such as architectural convergence, legacy migrations, or shared platform rollouts at scale - Exceptional systems thinking and problem-solving skills, with the ability to connect platform decisions to product quality, ML needs, and business outcomes - Strong communication skills, able to distill complex technical topics for senior technical and non-technical audiences - Bachelor's or Master's degree in Computer Science, Engineering, a related technical field, or equivalent experience

Benefits and work setup

- Base salary range: $242,634 – $499,541 USD, plus eligibility for equity - Hybrid work model: in-person collaboration 1–2 times per quarter from a Palo Alto or San Francisco office - Relocation assistance is not available for this role - US-based applicants only