System design interview questions with solutions

Common system design interview questions with sample discussions, code, and diagrams.

Solutions linked to content in the solutions/ folder.

Question
Design Pastebin.com (or Bit.ly)Solution
Design the Twitter timeline and search (or Facebook feed and search)Solution
Design a web crawlerSolution
Design Mint.comSolution
Design the data structures for a social networkSolution
Design a key-value store for a search engineSolution
Design Amazon's sales ranking by category featureSolution
Design a system that scales to millions of users on AWSSolution
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