A month-by-month path from fundamentals to interview-ready. Every step links to an interactive lesson you can run, not just read. The real goal isn't memorizing architectures, it's reasoning about tradeoffs out loud.
Get fluent in the building blocks, and when to reach for each.
The two tradeoffs every interview circles back to:
See them running in real systems:
Where senior candidates separate: what happens when the network splits.
Design for failure, not just the happy path:
Stop reading, start designing. Reproduce the classics, then build your own and get it scored.
Then prove it cold in the Builder: draw an architecture and have it scored on scalability, reliability, performance, and security.
Interviews probe whether you've run things in production.
Study how real outages happened and what fixed them in the war stories.
Designing under a 45-minute clock is a different skill. Practice it.
Senior interviews test how you think, not just what you know.
Can you break down an ambiguous prompt, state your assumptions, and defend a decision when challenged? Practice narrating your reasoning out loud on every system you study. That habit is the real differentiator.
The smallest real system, end to end. Hit play and watch a request flow through it.
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