Principal Backend Infrastructure Engineer - AI, Search & Knowledge Platforms

Principal Backend Infrastructure Engineer - Ai, Search & Knowledge Platforms

Do you want to make Apple products more intelligent for our users? The AIML Information Intelligence teams are building groundbreaking technology for algorithmic search and recommendation, machine learning, natural language processing, and artificial intelligence. The features we build are redefining how hundreds of millions of people use their computers and mobile devices to search and find what they are looking for. Apple's universal search engine powers search features across a variety of its products, including Siri, Spotlight, Safari, Music, App Store, Video, and many more. We are searching for a Principal Backend Infrastructure Engineer to define and drive the long-term technical strategy for our scalable, highly available, and robust search platforms. Build, evolve, and scale state-of-the-art infrastructure powering Apple's Search Platforms. Be a key technical leader contributing to the design, development, and operation of large-scale distributed systems. Work with machine learning researchers, backend engineers, and cross-functional teams to deliver step-function improvements in reliability, performance, and cost.

We design and build infrastructures to support features that empower billions of Apple search users. Our team processes trillions of links to find the best content to surface to users through search. We also analyze pages to extract critical features for indexing and ranking. We apply statistical analysis to improve crawling, extraction quality, web and knowledge graph data, link selection, freshness, retrieval performance, and many others. You'll have the opportunity to work with large-scale systems with trillions of rows, many petabytes of data, and real-time data pipelines with incredible complexity.

Minimum Qualifications

• 10+ years of experience leading and driving complex, ambiguous projects at company-wide scope
• Deep expertise in large-scale search and indexing systems, including hybrid lexical–semantic retrieval
• Strong background in distributed systems: highly available, low-latency, multi-region architectures
• Experience with AI and agentic systems, including knowledge platforms and retrieval-augmented generation (RAG)
• Strong coding skills and background in algorithms and data structures
• Experience with backend development, performance tuning, and testing
• BS, MS, or Ph.D. in Computer Science or a related field

Preferred Qualifications

• Experience with cloud services, Kubernetes, and cloud-native architectures
• Experience with real-time data and streaming platforms (Kafka, Flink, Pinot or equivalent)
• Experience with observability platforms including metrics, logging, and AI-assisted diagnostics
• Track record of driving reliability programs and reducing production incidents at scale
• Open-source leadership or community contributions in search, data, or infrastructure ecosystems
• Excellent interpersonal skills; able to work independently as well as influence across large organizations

At Apple, base pay is one part of our total compensation package and is determined within a range. This provides the opportunity to progress as you grow and develop within a role. The base pay range for this role is between $212,000 and $386,300, and your base pay will depend on your skills, qualifications, experience, and location. Apple employees also have the opportunity to become an Apple shareholder through participation in Apple's discretionary employee stock programs. Apple employees are eligible for discretionary restricted stock unit awards, and can purchase Apple stock at a discount if voluntarily participating in Apple's Employee Stock Purchase Plan. You'll also receive benefits including: Comprehensive medical and dental coverage, retirement benefits, a range of discounted products and free services, and for formal education related to advancing your career at Apple, reimbursement for certain educational expenses — including tuition. Additionally, this role might be eligible for discretionary bonuses or commission payments as well as relocation. Learn more about Apple Benefits Note: Apple benefit, compensation and employee stock programs are subject to eligibility requirements and other terms of the applicable plan or program. Apple is an equal opportunity employer that is committed to inclusion and diversity. We seek to promote equal opportunity for all applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, Veteran status, or other legally protected characteristics. Learn more about your EEO rights as an applicant At Apple, we believe accessibility is a fundamental human right. You'll find that idea reflected in everything here — in our culture, our benefits and our digital tools. By welcoming as many perspectives as possible, we help you build a career where you feel like you belong. Learn about accessibility in Apple's workplace Learn about reasonable accommodations for job applicants Apple accepts applications to this posting on an ongoing basis.