System Design

This round is not graded on the finished diagram. It is graded on the order you drew it in, the question you asked before the first box, and what you said while the pen was moving. A finished architecture picture teaches none of that — it hands you the destination with the reasoning already thrown away.

So these boards are locked. Nothing drags, nothing connects, nothing edits. Each one opens full screen, the way the circuit does: you step forward and the drawing assembles itself one move at a time, each with the decision that motivates it and the line you would say out loud. The reference travels with the board — requirements, the arithmetic worked in public, the trade-offs with what they cost, and the failures worth naming before the interviewer does.