LeetCode tells you you're wrong in 2 seconds. System design lets you find out in the interview.

algoSD fixes that. Drag in load balancers, app servers, caches, databases, queues, and CDNs. Wire them together and hit simulate. Traffic flows through your design, and anything that can't keep up turns red.

Then an AI interviewer reads what you actually drew and asks the follow-ups a real interviewer would: "Your DB is at 140% load. What now?" or "What happens when this cache goes down?"

• 35+ problems, from URL shortener to Uber and Netflix

• Reference design for every problem to compare against

• Scored on scalability, availability, latency, cost, and trade-offs

• Free, no signup, runs in the browser

Built it because system design prep has no feedback loop. Would love to hear what breaks, in your design or in mine.