Sr. Software Engineer - Fullstack

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.

We are looking for a Senior Software Engineer – Full Stack with 6+ years of professional software development experience to help build a new, scalable authentication platform.   You will work across the full stack, with a stronger focus on frontend development, while contributing to backend services, system design, architecture, deployment, and production support. This is an opportunity to join a new team and help shape a greenfield product from the ground up.

The Authenticity Guarantee program helps build trust in high-value transactions by having eligible items inspected for authenticity and quality before reaching the buyer. Our team is building Authentication as a Service , evolving these capabilities into a scalable and reusable platform that can support experiences beyond the core eBay marketplace, starting with Depop.   This is a new team working on a 0→1 product , with significant opportunities to influence architecture, technology choices, and how the platform is built.

Design, build, test, deploy, and maintain full-stack applications, with a focus on frontend development. Develop modern web experiences using React, Angular, or similar frontend frameworks. Design and build backend services and RESTful APIs. Design and work with relational databases such as PostgreSQL or MySQL. Build and deploy cloud-native applications using GCP, AWS, or Azure. Own complex features end-to-end, from technical design and implementation through deployment and production support. Contribute to system design and architecture, evaluating technical approaches and trade-offs as the platform evolves. Build high-quality, maintainable software and contribute to strong testing, code review, CI/CD, and production practices. Collaborate closely with product, UX, QE, and other engineering teams to drive technical decisions and delivery. Use AI-assisted development tools to improve engineering productivity while maintaining strong code quality and review practices. Evaluate technologies and frameworks and help establish engineering practices for the new platform. Provide technical guidance and mentorship to other engineers as the team grows.

6+ years of professional software engineering experience building production applications. Strong full-stack development experience, with significant hands-on frontend development. Experience with a modern frontend framework such as React, Angular, Vue.js, or similar. Experience designing and developing backend services and RESTful APIs. Strong programming skills in a backend language such as Java, Kotlin, C#, Python, Go, or similar. Experience designing and developing applications using relational databases such as PostgreSQL or MySQL. Experience developing and deploying applications in a cloud environment such as GCP, AWS, or Azure. Experience with CI/CD pipelines such as Jenkins, GitHub Actions, or similar. Experience contributing to system design and architectural decisions, including evaluating technical trade-offs. Experience independently owning technical problems from design through production. Experience using AI-assisted software development tools to improve developer productivity, with the ability to review and