How I simulated a Distributed System in the Browser

Building distributed systems is hard. Understanding their behavior under load is even harder. What if you could design, configure, and stress-test a distributed system architecture without spinning up a single server? That's exactly what I built—a fully interactive distributed system simulator that runs entirely in your browser. The Problem: Learning System Design is Abstract When preparing for system design interviews or architecting real-world systems, we often sketch boxes and arrows on whiteboards. "Put a load balancer here, add a cache there, maybe throw in some message queues for async processing." But how do you really know if your design will handle 10,000 requests per second? What happens when a database replica fails? Where will the bottlenecks appear? Traditional approaches require either: Production experience : Learn by breaking things in prod (not recommended) Complex local setups : Docker compose files with dozens of services Mental simulation : "I think this should work