Category · 9 articles

System Design

From URL shorteners to global feeds — designed end to end.

Deep-dives on cache, queue, replica, shard, and consistency tradeoffs. L4 to Staff+ scope, with real diagrams and capacity math.

  • system design interview
  • leetcode system design
  • neetcode system design
  • hackerrank system design
  • scalability interview
  • design twitter
19 min read3,712 words

Design a URL Shortener: IDs, Redirects, and Hot-Key Reality

From base62 counters to contention — a loop-friendly walkthrough with math you can say out loud.

  • system design interview
  • design url shortener
  • scalability interview
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18 min read3,668 words

Design a Chat System: Delivery Semantics and Presence at Scale

WebSockets, retries, and why exactly-once delivery is a myth you should not casually promise.

  • system design interview
  • chat system design
  • messaging system design
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19 min read3,750 words

Design a Distributed Cache: Eviction, Coherency, and Stampede Control

Memcached vs Redis patterns, single-flight, and what 'TTL' implies for your consistency story.

  • system design interview
  • distributed cache design
  • redis interview
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18 min read3,655 words

Design a Payment Ledger: Idempotency, Double-Entry, and Reconciliation

Financial correctness beats microservice fashion — start from invariants, not diagrams.

  • system design interview
  • payment system design
  • ledger design
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18 min read3,666 words

Design a News Feed: Fan-out, Ranking, and the Consistency Spectrum

Push vs pull, hybrid fan-out, and why 'real-time' is a product claim, not a default.

  • system design interview
  • design twitter
  • news feed system design
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19 min read3,701 words

Design a Video Streaming Platform: Encoding, CDN, and Playback QoS

Adaptive bitrate, segment storage, and DRM-adjacent concerns without Hollywood jargon.

  • system design interview
  • video streaming design
  • cdn interview
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18 min read3,689 words

Design a Distributed Rate Limiter: Tokens, Leaks, and Shared State

Edge vs service limits, approximate counters, and what breaks under Redis failover.

  • system design interview
  • rate limiter design
  • distributed systems interview
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18 min read3,679 words

Design Search Autocomplete: Tries, Ranking, and the Prefix Hotspot Problem

Latency budgets, personalization boundaries, and why caching prefixes is harder than it sounds.

  • system design interview
  • autocomplete system design
  • search system design
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10 min read1,676 words

System Design Interview Framework: The 7 Steps FAANG Loops Actually Score

Stop drawing boxes for forty-five minutes. Score the rubric the interviewer is filling out in real time.

  • system design interview
  • leetcode system design
  • neetcode system design
  • system design framework
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