.NET Day 2025: Tickets to Ride: Conquering Booking Chaos with Resilient .NET Architecture

Transcript

1. Tickets to Ride: Conquering Booking Chaos with Resilient .NET Architecture Steffi Erne .NET Day Switzerland 2025, 26. August 2025
2. Booking Train Tickets in Europe 2 many carriers each with their own unique quirks it's a jungle
3. 3 You develop your business. We develop your software. Discover Europe by train
4. Simplifying Complexity 4
5. Simplifying Complexity 5
8. Challenges 8 Every carrier does their own thing Many external systems → unreliability, bugs compound ❓ ❌ ⏳
9. 9 "Every carrier does their own thing"
10. CQRS & Event-driven Architecture 10 commands (mutations) write data - create events - projections convert events into domain data queries read data events = audit trail
11. Example: Book Order 11 1. 👤 User sends BookOrder command 2. 🔄 BookOrderMutation receives command 3. ⚙ OrderService calls external API 4. 🚂 External API confirms booking 5. 📝 OrderBooked event added to event store 6. 📡 Event dispatcher notifies handlers 7. 💾 Event handler projects to database
12. Order confirmation waiting for OrderBooked Event 12
13. DDD & Hexagonal Architecture 13 separation of domain and providers easy to add / switch providers DDD: Ubiquitous Language specific naming - OrderConfirmed instead of OrderUpdated → no CRUD
14. Resilience 14 Asynchronous Retry Fallback
15. What have we learned? 15 Design for Failure from Day One "What happens when this external system goes down?" Early Adopter Tax is Real "Are we ready to be guinea pigs for this platform?" Simple Patterns, Complex Problems "What's the simplest solution that could possibly work?"
16. 16 Thanks for coming along on the ride! 🚂 What do you get when you cross a locomotive with bubblegum? A chew-chew train Stefanie Erne Software Engineer @ nxt 💼 linkedin.com/in/stefanie-erne ✉ stefanie.erne@nxt.engineering
17. Christian Mäder Software Engineering und Geschäftsleitung Mirco Widmer Software Engineering und Geschäftsleitung Michael Gerber Software Engineering und Geschäftsleitung Christian Cremer Software Engineering Michael Reimer Software Engineering, Sales Stefanie Erne Software Engineering Team 23
18. nxt Engineering GmbH hallo@nxt.engineering https://nxt.engineering +41 44 508 52 45 Leutschenbachstrasse 45 CH-8050 Zürich Das Team von nxt freut sich auf die Zusammenarbeit!