Campus second-hand trading platform implements a five-phase product publishing workflow orchestrating student submissions, form validation, database persistence, asynchronous admin notifications, and result propagation. Student users submit product information through a ProductForm UI, which synchronously validates and persists data via a DataManager component, then triggers an asynchronous notification to Administrator for review. Administrators review products and update status back through DataManager, which propagates acceptance or rejection results to the student, enabling revision and resubmission on rejection. This sequence diagram demonstrates best practices for separating synchronous validation from asynchronous review workflows, reducing blocking operations and improving platform responsiveness. Fork this diagram on Diagrams.so to customize actor roles, add payment processing, or integrate notification services like email or SMS. The async notification pattern shown here scales well for high-volume submissions where admin review latency should not block user experience.