Senior Backend Engineer

At eBay, we're more than a global ecommerce leader — we’re changing the way the world shops and sells. Our platform empowers millions of buyers and sellers in more than 190 markets around the world. We’re committed to pushing boundaries and leaving our mark as we reinvent the future of ecommerce for enthusiasts. Our customers are our compass, authenticity thrives, bold ideas are welcome, and everyone can bring their unique selves to work — every day. We're in this together, sustaining the future of our customers, our company, and our planet. Join a team of passionate thinkers, innovators, and dreamers — and help us connect people and build communities to create economic opportunity for all. The Role We are reinventing advertising at eBay! As a Senior Backend Engineer in the Ads team, you will work closely with designers, product managers and other engineers (frontend, backend, native, machine learning, quality) to redefine the advertising space for eBay and beyond. We are innovating rapidly in the ad-tech space and there is no shortage of new challenges for motivated individuals. Our goal is to create a valuable experience for both buyers and sellers, while also driving performance through Ads Learn About Our Work eBay Advertising Insights: eBay AdvertisingPromoted Listings on eBay: eBay Seller Center - Promoted Listings Job Responsibilities Design new experiences for eBay sellers and advertisers to promote their products, manage their advertising campaigns, and run their businessesDevelop highly available, scalable RESTful APIs and event-driven systems processing billions of ad-serving and bidding events with strict latency and reliability requirementsDevelop systems using Java/Scala, Spring Boot, and Node.js across our microservices architectureImplement well-designed backend services following established architectural patterns, and contribute to design documents and technical reviews with peers and senior engineers.Understand and apply trade-offs in system design (consistency, availability, latency, cost) within your service areaLeverage AI-assisted development tools (e.g., GitHub Copilot, Claude Code) throughout the development lifecycle for coding, debugging, testing, and code review to increase engineering velocityContribute to AI-powered advertising features by collaborating with ML engineers on LLM integrations, recommendation systems, and intelligent campaign optimizationEvaluate and adopt new technologies—including AI-assisted tools—to improve system quality and engineering velocity.Operate within our internal open source community where we share a variety of projects and codebasesDevelop, test, and deploy services through automated CI/CD pipelines with a focus on reliability and observabilityWork effectively within a fast-paced, Agile team, adapting to evolving priorities and delivering iterative value to customersContribute to technical conversations and debates, and decide upon approaches and tools to apply Qualifications Job Requirements: BS/BA in Computer Science or related field with 7+ years of experience, or MS with 5+ years Backend Strong experience in Java (17+) and building services with Spring Boot or similar frameworksExperience building scalable backend systems and RESTful APIs in distributed environmentsExperience with event-driven architectures and message queues (Kafka, RabbitMQ, or similar)Experience with relational (Oracle/Postgres/MySQL) and/or NoSQL (Cassandra/MongoDB) databases, including schema design and query optimization System Design & Core Skills Strong system design experience for distributed, high-traffic applications (able to lead a 45-min system design interview)Ability to reason about system design trade-offs (e.g., consistency vs availability, sync vs async)Proven computer science fundamentals (data structures, algorithms) Other / Tools & Practices Experience with CI/CD tools (Jenkins, GitHub Actions)Strong ownership mentality with ability to drive work end-to-end in a collaborative environmentAbility to build LLM workflows or automation powered by artificial intelligence Nice-to-Haves ScalaExperience with Node.js and modern backend frameworks (Express, NestJS, Fastify)Exposure to GraphQL and experience in building Federated GraphQL APIs is highly desirable.Familiarity with columnar databasesContributions to open source, GitHub projects, or side projects Be Part of Our Vision: At eBay, we foster an environment where innovation, collaboration, and problem-solving thrive. If you're eager to contribute to the next generation of ad-tech solutions and have the skills we're looking for, especially your experience with GraphQL, we encourage you to apply. Share your GitHub profile and any relevant project work to demonstrate your capabilities. Additional Details The base pay range for this position is expected in the range below: C$142,400 - C$190,100 Base pay offered may vary depending on multiple individualized factors, including location, skills, and experience. The total compensation package for this position may also include other elements, including a target bonus and restricted stock units (as applicable) in addition to a full range of medical, financial, and/or other benefits (including RRSP eligibility, various paid time off benefits, such as PTO and parental leave). Details of participation in these benefit plans will be provided if an employee receives an offer of employment. This job posting relates to an existing vacancy within eBay. eBay is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, sex, sexual orientation, gender identity, and disability, or other legally protected status. If you have a need that requires accommodation, please contact us at talent@ebay.com. We will make every effort to respond to your request for accommodation as soon as possible. View our accessibility statement to learn more about eBay's commitment to ensuring digital accessibility. We use cookies to enhance your experience and may use AI tools for administrative tasks in the hiring process. To learn how we handle your personal data and use AI responsibly, please visit our Talent Privacy Notice, Privacy Center and AI Hiring Guidelines.