Real World Extraction

Full system-design briefs. More than one architecture passes.

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First contact with open briefs while Part 3 is still in progress - tiny surfaces, one crisp new problem each.

The first multi-subsystem projects: every piece is familiar on its own, and the composition is the lesson.

Full products with two or more interacting subsystems and real consistency stakes.

The interview canon's centerpieces - each inverts or stresses a foundational assumption.

Deep single-problem systems: each takes one hard sub-problem and makes it the whole project.

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Tier 1 · Foundational Systems

~75 min

How this works

Apply what you've learned to a full system design problem.

Each tier assumes the Building Blocks chapters behind it, so work across a domain in order.

A failed check always explains why. Hints stay optional - ask for one only if you want it.