Backend system design interview questions
Estimates, layering, monolith or microservices, and full designs: URL shortener, news feed, chat, payments, rate limiter service, autocomplete and file storage.
– interview-ready · 10 questions in this topic
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Questions
- Back-of-the-envelope estimatesPredict
- Layering a backend servicePick the fix
- Monolith or microservicesPick the fix
- Design a URL shortenerPredict
- Design a news feedPick the fix
- Design a chat backendOrder the steps
- Design a payment flowPredict
- Design a distributed rate limiterPick the fix
- Design search autocompletePick the fix
- Design file uploads and storagePick the fix
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Flashcards · 14
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Quick quiz · 10 questions
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Mock interview · 2 sets
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Quick facts
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Seconds in a month
30 × 24 × 3,600 = 2,592,000, about 2.6 million.
Base62 length 7
62⁷ = 3,521,614,606,208 possible codes.
0.1 + 0.2
In binary floating point it equals 0.30000000000000004, so money uses integers or Decimal.
Strangler fig
Replace a legacy system piece by piece by routing one capability at a time to new code.
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Sources: Topic outline informed by System Design Primer by Donne Martin and the Zalando RESTful API Guidelines, both licensed under CC BY 4.0. Every question and answer is written by Best Latest Apps. Credits and license