Backend Software Engineer, AI Platform

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 DEX team builds eBay’s Decisioning & Execution Engine, the platform that powers automated decisions and guided judgment for Customer Service and risk workflows across online and batch channels. We provide an intuitive rules and model-based engine that evaluates billions of evaluations per year, orchestrating actions for multiple internal clients and tools.

We’re looking for a full-time software developer who will help evolve DEX into a more AI-native decisioning platform, integrating machine learning models, LLMs, and experimentation into our core flows.

What You’ll Do

Design, implement, and maintain backend services and APIs that power DEX decisioning in both real-time and batch modes.

Build and integrate ML- and LLM-driven decisioning components (e.g., model inference, feature computation, policy orchestration) into existing rules flows.

Collaborate with data scientists and rule analysts to productionize models, define interfaces, and deploy decision logic safely at scale (including A/B and canary rollouts).

Extend our rules and configuration framework so that policy and operations teams can safely author, test, and deploy sophisticated decisions without code changes.

Partner with product and partner teams (e.g., Customer Support, Risk, Trust, Billing, Returns) to translate business policies into robust, measurable technical solutions.

Participate in code reviews, architecture discussions, and on-call for the services you own.

You are

A backend engineer with strong experience in at least one strongly typed language (e.g. C#, Java or similar) and building distributed services in production.

Comfortable working with SQL datastores, designing schemas, and writing performant queries for high-volume flows.

Experienced with AI/ML in production – e.g., integrating models behind APIs, working with feature pipelines, or building inference services (Python, model-serving frameworks, etc.).

Familiar with (or eager to learn) LLM-based applications: prompt design, retrieval-augmented workflows, guardrails, and human-in-the-loop feedback.

Strong in systems thinking: you care about latency, throughput, resilience, and the blast radius of changes in high-volume decision systems.

Comfortable working in a highly collaborative environment with product managers, analysts, and operations partners, and explaining complex technical concepts in clear language.

Basic Qualifications

BS in Computer Science, Engineering, or equivalent practical experience.

4+ years of software development experience (or equivalent), with a focus on backend or platform engineering.

Experience building and owning production services (REST/JSON or gRPC) and working in CI/CD environments.

Experience with at least one cloud or large-scale infrastructure environment.

Demonstrated experience integrating machine learning or advanced analytics into user- or system-facing products.

Preferred Qualifications

Experience with decisioning/rules engines, workflow engines, or policy automation platforms.

Hands-on experience with ML/AI contexts (data pipelines, model training, evaluation, or inference).

Experience with LLM frameworks (e.g., LangChain, semantic search, RAG) or prior work on AI assistants for internal tools.

Familiarity with customer service, risk, or trust & safety domains.

Experience in high-availability, multi-region services and designing for resilience, monitoring, and alerting.

Why this role

This is an opportunity to shape the next generation of eBay’s decisioning platform, bringing together rules, ML, and LLMs to drive better automation, guidance, and outcomes for customers and teammates. You’ll work on a critical, high-visibility system with strong business impact and a team that invests deeply in quality, safety, and innovation.

Additional Details