How One Shop Survives a Million Users (Redis, Kafka, Sharding Explained)
How does an app that works for ten people survive a million? The fix is not a faster computer. In five minutes we sketch the whole map of how modern data systems actually fit together, using one village shop that learns to handle a crowd. By the end, every intimidating phrase (Redis, Kafka, sharding, consensus, Spark, vector search) is just one move on a napkin.
Chapters
00:00 The app that catches fire
00:51 One shop: how every app starts
01:17 The counter shelf (caching, aka Redis)
01:54 More hands (replication)
02:41 More stores (sharding)
03:22 Getting them to agree (consistency and consensus)
04:10 Making sense of the chaos (Kafka, Spark, warehouses, vectors)
05:19 The whole map
05:39 Where to start next
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