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System design, learned through real production scenarios.

For .NET developers growing into senior, lead and architect roles.

Each drop puts you inside a .NET and Azure system when something goes wrong in production. You pick how to fix it. Then you see which answer was right, and why the other options would fail.

You pick how to fix a .NET and Azure system that breaks in production, then see why each option works or fails.

Latest · Drop 13 · October 2026 .NET + Azure
This drop
RoomBay

RoomBay is a hotel booking platform where guests search by city and dates, pick a room, and pay to book. About 40,000 hotels use it...

8 scenarios · about 5 minutes
Start

After every drop you get your score, a study link for each scenario you missed, and a certificate if you score 85% or above. See an example

All drops
  • Drop 12 · October 2026 .NET
    8 scenarios from HireBoard, a job portal.
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  • Drop 10 · September 2026 .NET + Azure
    8 scenarios from CartLane, an online shopping platform.
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  • Drop 09 · September 2026 .NET + Azure + AI
    8 scenarios from AskDesk, an AI customer support assistant.
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  • Drop 08 · August 2026 .NET + Azure
    8 scenarios from StreamDock, a video streaming app.
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  • Drop 07 · August 2026 .NET + Azure
    8 scenarios from TapRide, a ride-hailing app.
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  • Drop 06 · August 2026 .NET + Azure
    8 scenarios from QuickBite, a food delivery app.
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  • Drop 05 · July 2026 .NET + Azure
    6 scenarios: pipeline order, secrets, poison messages, retries, service auth, and partial failures
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  • Drop 04 · July 2026 .NET
    6 scenarios on ASP.NET Core applications
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  • Drop 03 · July 2026 .NET
    10 system design scenarios from building a railway ticket booking application
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  • Drop 02 · July 2026 .NET
    Cache stampedes, backpressure, CQRS, GDPR, security and more · 10 scenarios
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  • Drop 01 · July 2026 .NET
    Slow queries, caching, cascading outages, deployments and more · 10 scenarios
    Start
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