Nine patterns, and where the complexity goes
Nine distributed systems patterns, written the way they actually get decided: what you buy, and where the complexity goes. Because none of these remove complexity. They relocate it. Replication. Multiple copies, one writer. You buy availability and read throughput. You now own replication lag, and the ticket from a user who saved something and didn’t see it on refresh. Sharding. Split the data across databases. You buy headroom. You now own a shard key that you chose at the exact moment you knew least about your traffic. ...