The dojo for distributed systems
Watch real systems fail.
Build one that holds.
Real incidents reconstructed as playable challenges. Design the architecture, run the simulation, see if it survives.
Single-Region Web App
Classic 3-tier web app with synchronous request chain.
Service Cascade
Gateway calling internal and external services in parallel.
Social Platform API
Separated read and write paths behind an API gateway.
Telemetry Ingestion Pipeline
Queue-buffered ingestion with async consumers.
Read-Replica Scaling
Read-heavy traffic distributed across replicas with async replication.
Active-Passive Regional Failover
Geo router with warm standby and automatic failover.
Global E-Commerce Marketplace
Two-region marketplace with single-primary write asymmetry.
Video Streaming Platform
Three-region CDN with centralized entitlement checks.
Payment Processing Platform
Multi-region payments with method-dependent SLAs.
Real-Time Messaging Platform
Broadcast-based messaging with cross-region replication.
Scatter-Gather Search
Parallel shard queries with results cache.
Identity & Token Validation
Token validation with high-hit-rate cache shielding the DB.
Event-Driven Order Saga
Queue-choreographed order processing with isolated consumers.
Multi-Channel Notification Hub
Per-channel queues isolating push, email, and SMS delivery.
Multi-Tier CDN with Origin Shield
Edge caches + origin shield protecting a single origin DB.
CI/CD Pipeline
Serial build-and-deploy pipeline with queue-gated stages.