An AI interviewer that watches you draw and listens to you think. Real-time follow-ups. Seniority-calibrated questions. Honest feedback in seconds.
You've designed the write path. Let's stress-test it — at 50,000 writes per second, your single Kafka topic becomes a bottleneck. |
Candidate is drawing on the whiteboard…
YOUHow It Works
Pick a classic — URL shortener, ride-sharing backend, distributed cache, or bring your own. Set your target seniority level.
Speak your approach. Draw on the whiteboard. The AI listens, watches, and intervenes with targeted follow-ups when you go quiet.
End the session and receive a full evaluation with scores, strengths, concrete improvements, and a seniority verdict in seconds.
Sample questions by level
"Walk me through what a load balancer does before we scale this."
"You've mentioned sharding. What's your strategy for hot partitions?"
"At 10M writes/day, your single Postgres node is a problem. How do you migrate with zero downtime?"
"Other teams depend on this API. How do you version it while rolling out the new schema?"
"The board wants 5-nines. Walk me through your runbook if the primary region fails during peak."
Why DesignLoop
Not a chatbot. Not a quiz. A full simulation — voice, whiteboard, follow-ups — that behaves like the interviewer you dread.
Draw your architecture in Excalidraw. The AI watches in real-time and incorporates your diagram into every follow-up question — just like a real interviewer who's actually looking at your drawing.
L3 engineers get scaffolded through the basics. Staff and Principal candidates face API contract challenges, cascading failure scenarios, and cross-org tradeoff decisions. The bar adjusts automatically.
AI responses are delivered as natural speech via text-to-speech. No reading walls of text. Hear the follow-up, think, draw, answer — the same rhythm as a real 60-minute loop.
After every session, get a detailed breakdown: Scalability, System Design, Communication, Trade-off Reasoning, and an honest Seniority Assessment. With specific examples from your session.
Post-Session Feedback
Overall Score
Strengths
Improve
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