Senior Node.js Engineer

• Marketing Technologies Platform

About e Bay

At e Bay, 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.

Team Overview

Join the Marketing Technologies Platform Team that powers billions of customer interactions per day. This team builds and scales intelligent communication systems, integrating cutting-edge AI to deliver personalized and timely engagement experiences across e Bay's global user base.

Role Overview

We are looking for an experienced and highly motivated Senior Node.js Engineer with a strong background in developing scalable web services and AI-powered applications. You will play a central role in designing, developing, and maintaining APIs and backend systems that integrate with large language models (LLMs), agent frameworks, and advanced AI technologies. This role is ideal for engineers who are passionate about building the future of AI applications.

Key Responsibilities

• Backend Development: Design, develop, and maintain high-performance, scalable Node.js services for real-time AI-driven applications.
• AI Integration: Implement systems that interact with AI models and services such as OpenAI (GPT), Anthropic (Claude), and others.
• Agent Frameworks: Apply agent design patterns and leverage frameworks like Lang Graph and Lang Chain to orchestrate multi-step workflows and reasoning tasks.
• Prompt Engineering & RAG: Develop robust prompt interfaces, retrieval-augmented generation pipelines, and context-aware query structures.
• Model Context Protocol (MCP): Design and implement context-aware AI services leveraging the Model Context Protocol for effective orchestration and input management.
• System Design: Architect distributed systems that are secure, fault-tolerant, and horizontally scalable.
• Collaboration: Work with data scientists, product managers, and fellow engineers to translate requirements into technical deliverables.
• Testing & CI/CD: Implement unit tests, integration tests, and maintain CI/CD pipelines for deployment and automation.
• Documentation: Contribute to technical documentation, system diagrams, and design specifications.
• Code Review & Mentorship: Participate in peer reviews and provide guidance to junior developers.

Qualifications

Required

• Education: Bachelor's or Master's degree in Computer Science, Engineering, or a related technical discipline.
• Experience: 6+ years of experience in backend development with a focus on Node.js and JavaScript/TypeScript.
• APIs & Protocols: Expertise in building and consuming RESTful and GraphQL APIs.
• Databases: Strong proficiency in relational and NoSQL databases (e.g., PostgreSQL, MongoDB).
• Cloud: Experience with cloud-native development on AWS, GCP, or Azure.
• AI Technologies: Hands-on experience integrating with LLMs (e.g., GPT, Claude), embedding models, vector databases (e.g., Pinecone, Weaviate, FAISS), and prompt engineering techniques.
• Agent Systems: Solid understanding of agent frameworks, tools, and design patterns for autonomous AI behavior.
• Security: Knowledge of API authentication, authorization (OAuth, JWT), and security best practices.

Preferred

• Experience with Lang Chain, Lang Graph, Semantic Kernel, or similar orchestration frameworks.
• Familiarity with front-end frameworks (React, Vue) is a plus.
• Knowledge of event-driven architectures and message queues (e.g., Kafka, RabbitMQ).
• Experience with containerization and orchestration (Docker, Kubernetes).
• Familiarity with MLOps workflows and model lifecycle management.
• Exposure to observability tools (e.g., Datadog, Prometheus, Open Telemetry).

Why Join Us

If you're excited about the intersection of high-scale engineering and cutting-edge AI, and you're driven to build the next generation of intelligent applications, we encourage you to apply.

Equal Opportunity

e Bay 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, veteran status, 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 e Bay's commitment to ensuring digital accessibility for people with disabilities.