Guided practice

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

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  3. Design a Distributed Cache

  Partition cached data, survive node loss and keep cache misses from overwhelming the source of truth.

  ClassicMedium

  CachingShardingDatabases

  +9

  Distributed systemsAWSConsistencyConsistent hashingHot keysLRU evictionMemcachedRedisReplication

  Worked design

  Practice
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  41. Ad Click Aggregator: Low-Level Design

  The classes and code behind the ad click aggregator: signed click tokens, a redirect that never waits on the log, and a stream counter that de-duplicates and handles late clicks. Tests run all of it.

  Data engineeringMedium

  ShardingStreamingDistributed systems

  +6

  HMACHot keysIdempotencyLow-level designTypeScriptWatermarks

  Worked design

  Practice

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