The Ticketmaster Problem

The Perfect Storm

Imagine a popular concert goes on sale at 10:00 AM. Within seconds, hundreds of thousands of users flood the site simultaneously.

Every single one wants the same thing: a ticket. But there are only 20,000 seats.

Three Core Challenges

This system must solve three problems at once:

1. Extreme burst traffic — Handle 500K+ concurrent users for a single event, when normal traffic might be 1,000.

2. Inventory consistency — Never sell the same seat twice, even when thousands click "buy" at the same instant.

3. Fairness — Users who arrived first should get priority.

Why This Is Different

Most systems handle traffic that's spread out over time. A social media feed serves millions, but they arrive gradually.

Ticketmaster is different. Traffic arrives all at once — a massive spike in seconds. And unlike a social post (shown to everyone), each ticket can only be sold once.

What We'll Build

Over this course, you'll design a complete ticket booking platform:

• Foundation — Requirements, entities, API, architecture overview
• Search & data flow — Elasticsearch, CDC, caching
• Booking & consistency — Distributed locking, seat holds, database safety
• Burst traffic — Virtual waiting room, rate limiting
• Putting it together — Payment, failure handling, the complete picture

Each technology is introduced when you need it to solve a specific problem.