Design a Auction System for eBay

Functional Requirements:

• User Registration & Authentication: Users can sign up, log in, and manage their accounts.
• Item Listing: Users can create auction listings with item details, images, starting price, and auction duration.
• Bidding: Users can place bids on active auctions. Only bids higher than the current highest bid are accepted.
• Auction Lifecycle: Auctions have a clear start and end time. The highest valid bid at the end wins.
• Notifications: Users receive notifications for key events (e.g., outbid, auction won/lost).
• Auction History: Users can view their past auctions and bids.
• Payment Handling: System supports payment processing for winning bids.

Non-Functional Requirements:

• Scalability: System should handle spikes in bidding activity, especially near auction end times.
• Reliability: Auctions must end at the correct time and determine the winner accurately.
• Security: User data and transactions must be protected. Only authorized users can bid or list items.
• Performance: Real-time bid updates and low-latency responses for user actions.
• Usability: Simple and intuitive interface for both buyers and sellers.
• Maintainability: Codebase and infrastructure should be easy to maintain and extend.