Curated coding patterns, system design frameworks, and company-specific guides — built for busy engineers who want signal, not noise.
Most engineers fail on one of three fronts: pattern recognition under time pressure, system design fluency, or company-specific expectations. We cover all three.
The 15 patterns that cover roughly 80% of medium-difficulty coding interviews. Drill the patterns, not 500 random problems.
Explore patternsA repeatable framework for breaking down design problems, the building blocks every system uses, and worked-through case studies.
Learn the frameworkWhat each loop looks like, what the company actually evaluates, and what to study. Specific, actionable, no fluff.
See company guidesWe drop everything that hasn't shown up in a real interview in years. Every page is signal-dense.
Recognizing the pattern in 60 seconds beats grinding 500 problems. We teach pattern recognition.
System design isn't memorizing diagrams — it's a framework for reasoning under pressure. We give you that framework.
No paywalls, no upsells, no email gates. Just open the handbook and start reading.
The handbook opens with a 5-minute orientation. You'll know exactly where to focus by the end of it.
Open the Handbook