April 2026 - Duration 20 Days
The Haxoniq Challenge: The Million-Seat Flash Sale
Deadline
Join the challenge, the clock is ticking!
Join now for
A chance to win a $ voucher Prize
Check the evaluation criteria below to know how
700$
200$
Second Place
100$
Third Place
The Scenario
The Mission
Build a High-Performance Booking Application that will handle this traffic.
Your system must ingest a chaotic stream of purchase requests, assign seats, process payments, and update the stadium map in real-time,
without selling the same seat twice.
without selling the same seat twice.
The Challenge
We aren't looking for a pretty e-commerce website. We are looking for a Ferrari-grade backend engine.
1. The Scale
- Inventory: 1,000,000 specific seats (Section, Row, Seat Number).
- Load: You must process a simulated stream of 10,000 requests per second.
- Goal: Sell out the entire stadium in under 10 minutes while maintaining 100% data consistency.
2. The Hard Constraints (The "Why It Breaks")
- The "Highlander" Rule: Every seat must have exactly one owner. Zero double bookings allowed.
- The "Squad" Rule: Users buy up to 4 tickets at once. They must be adjacent (e.g., A1, A2, A3, A4). If A3 is taken, the whole group fails. You cannot split groups.
- The "Wallet" Atomicity: Each user has a prepaid wallet. You must atomically reserve the seats AND deduct the funds. If one fails, both roll back.
The Deliverables
You must submit a single application repository containing two parts:
A. The Core Engine (Backend)
- This is where you win or lose.
- Input: An HTTP/WebSocket endpoint that accepts a high-velocity stream of BookTicketCommands.
- Logic: The "Black Box" that enforces the rules above.
- Output: A stream of confirmed TicketSoldEvents.
- Tech Stack: Java/Kotlin is preferred. Use of Axon Framework and Axon Server is highly recommended to handle the distributed state and event sourcing.
B. The Operational Dashboard (Frontend)
- Philosophy: Function over Form. We don't care about CSS, logos, or animations.
- Requirement: A single-page "Heatmap" of the stadium.
- Gray: Available
- Red: Sold (Updates live via WebSocket/SSE)
- Yellow: Reserved/Pending
- Why? To prove your app is actually working in real-time during the stress test.
Evaluation Criteria
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Consistency 40%
-
Throughput 30%
-
Architecture 20%
-
Visuals 10%
You will benefit the most if you are a Senior/Junior Developer
New to Event-Driven architecture and Event-sourcing.
Already using Axon Framework and/or Axon Server.
Meet our Judges
Panel of expert developers
During the hackathon, our developers and solution architects, and builders of the Axoniq Platform will be grading and providing feedback for your challenge submissions.
The Haxoniq Challenge: The Million-Seat Flash Sale
