Open SystemDecoder on a larger screen to build systems, run simulations, and inject chaos.
What's waiting for you on desktop
Live Simulations
Watch latency spike, queues fill, and nodes fail in real time. Every slider change is instant.
Visual Architecture Canvas
Drag nodes, draw edges, and build any distributed system topology from scratch.
Chaos Engineering
Kill servers, introduce packet loss, throttle CPUs — and watch your system react.
Real-time Insights
Throughput, p99 latency, error rates — all charted live as your simulation runs.
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"The best way to understand a distributed system
is to break it."
📸
100M photos uploaded daily
How does Instagram serve them all in <50ms?
Instagram serves 500 million daily active users. At peak, 100 million photos are uploaded every day. How does the system store, process, and serve all of them in under 50ms?
Why We Need This
Over the next steps you'll build Instagram's media infrastructure from scratch — starting with the naïve approach that broke in production, then layering on S3 storage, pre-signed uploads, async processing pipelines, CDN delivery, and Redis-cached feeds.
Key Insight
Instagram's media stack is a masterclass in separating concerns: object storage for files, CDN for delivery, async workers for processing, and Redis for feed reads.
Overview