PayTrack is a 3-tier client-server financial tracking application separating presentation, business logic, and data layers for scalability and maintainability. User interactions flow from the web browser through login, dashboard, and reporting interfaces in the presentation layer, then route through authentication, transaction management, and financial processing modules in the application layer, with all state persisted in a relational database. This architecture demonstrates separation of concerns and enables independent scaling of frontend, backend, and database tiers—critical for fintech applications handling sensitive user data. Fork this diagram on Diagrams.so to customize it for your AWS deployment, add API Gateway and Lambda functions, or extend it with additional microservices. The four-phase sequence (authentication, transaction entry, financial processing, reporting) maps directly to typical user workflows in personal finance and expense management systems.