Functional
Understanding functional requirements in system design.
Functional Requirements
Functional requirements describe what the system must do — the features, behaviors, and user interactions. Another way to say it: Business capabilities User-facing features System actions
User Management Sign up Login / logout Reset password Update profile Delete account
E-commerce Search products Add to cart Place order Cancel order Track shipment
Example with future Content:
Example: URL Shortener Must: Shorten URL Redirect alias should be of 6 character(1-9) and(A-z) Nice: Custom alias Click analytics Future: Expiry Geo stats
How Functional Requirements connect with System Design
| Functional Requirement | Design Impact | | ---------------------------- | ----------------------- | | Send message | Message service + API | | Receive message in real-time | WebSockets | | Send images | Object storage (S3) | | Message history | Database schema | | Read receipts | Extra metadata + events |
Example : chat application