High level design, for interviews and for building things

Study System Design. Worked out.

You have a job, and a Senior or Staff interview somewhere in the next few weeks. An hour in the evening is about what you have got, so each article is one sitting: one system, walked the whole way.

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Argued from the papers and the postmortems, not from blog posts.

Cache hit rate

hit rate: 99.0 %
multiplier, 1 / (1 − h): 100x
database normally: 1,000 /s
if the cache dies: 100,000 /s

At 100,000 requests a second. Drag it: the multiplier is the whole argument, and it is one division.

Every decision here is argued with a diagram.

Problem Breakdowns

One system, designed end to end, the way a 45 minute interview goes.

Core Concepts

The building blocks behind the designs. Every answer is worked out, not just stated.

01Caching Strategies and InvalidationNeeded byURL Shortener
- 69 min read

Patterns

Ideas that come up again and again. Explained once, linked from every article that uses them.

More coming soon.

Study System Design. Not memorised.Worked out.Not memorised.End to end.

Problem Breakdowns

Core Concepts

Patterns

Study System Design. Worked out.