Staff Engineer - Backend (Post Purchase Experience)

Company Introduction We exist to wow our customers. We know we’re doing the right thing when we hear our customers say, “How did we ever live without Coupang?” Born out of an obsession to make shopping, eating, and living easier than ever, we’re collectively disrupting the multi-billion-dollar e-commerce industry from the ground up. We are one of the fastest-growing e-commerce companies that established an unparalleled reputation for being a dominant and reliable force in South Korean commerce. We are proud to have the best of both worlds — a startup culture with the resources of a large global public company. This fuels us to continue our growth and launch new services at the speed we have been since our inception. We are all entrepreneurs surrounded by opportunities to drive new initiatives and innovations. At our core, we are bold and ambitious people that like to get our hands dirty and make a hands-on impact. At Coupang, you will see yourself, your colleagues, your team, and the company grow every day. Our mission to build the future of commerce is real. We push the boundaries of what’s possible to solve problems and break traditional tradeoffs. Join Coupang now to create an epic experience in this always-on, high-tech, and hyper-connected world. Role Overview The C-Returns Platform team owns the end-to-end lifecycle of cancellations, returns, and exchanges for Coupang's e-commerce ecosystem. We process millions of post-purchase resolution requests through our customer facing Coupang App and CS/back-office channels, serving both Korea and Taiwan markets. Our platform is mission-critical infrastructure that directly impacts: Customer satisfaction — making post-purchase resolution fast, transparent, and predictable Inventory protection — minimizing inventory loss through structured collection logistics, QA inspections, and time-bound auto-withdrawal policies Business agility — enabling rapid policy changes through event-driven architecture with visibility and adaptability What You Will Do Build and maintain Tier 1 & Tier 2 services that handle 500K+ requests/day across multiple microservices Design and implement complex business workflows using Activiti BPMN and Temporal Cloud for orchestrating cancellations, returns, exchanges, and refunds Integrate with 15+ upstream and downstream systems including Order, Shipment, Payments, Transport. Implement policy-driven business logic that adapts to frequently changing cancellation, return, and refund rules Basic Qualifications 7+ years of backend software engineering experience Strong proficiency in building distributed systems and microservices architecture Experience with high-throughput, low-latency systems handling millions of requests Experience with event-driven architectures using Kafka or similar messaging systems Strong problem-solving skills and ability to debug complex distributed systems Excellent collaboration skills to work with cross-functional teams (Product, CS, Logistics, Payment) Preferred Qualifications Backend development (Java, Kotlin, or similar JVM languages preferred) RESTful API design and implementation Database design and optimization (MySQL, Aurora) Message queue systems (Kafka) Workflow engines (Activiti BPMN, Temporal) Monitoring and alerting (Grafana, CloudWatch) Version control (Git) CI/CD tools (CircleCI or similar) Type of work model Hybrid / Onsite / Remote working Our Hybrid work model: Coupang hybrid work model is designed to enable a culture of collaboration that acts a catalyst to enrich the experience of employees. Employees are required to work at least 3 days in the office per week, with the flexibility to work from home 2 days a week, depending on the role requirement. Some businesses may require more time in office due to nature of work. Details to consider Those eligible for employment protection (recipients of veteran’s benefits, the disabled, etc.) may receive preferential treatment for employment in accordance with applicable laws. P