Guided practice

Company tags are community-reported. Counts on cards show how many people reported that design.

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  92. Design Online Chess

  Real-time rated chess with server-validated moves, lag-compensated clocks, pairing by rating and a million watchers on one game.

  ClassicMedium

  DatabasesAWSDynamoDB

  +4

  GamingMatchmakingRatingsWebSockets

  Worked design

  Practice
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  93. Design a Real-Time Game Leaderboard

  Rank 200 million players in real time with sharded Redis sorted sets, count every game exactly once, and close a season fairly.

  ClassicMedium

  CachingDatabasesStreaming

  +8

  Distributed systemsAWSFlinkGamingKafkaLeaderboardsRedisSorted sets

  Worked design

  Practice

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