Caching in System Design - The Secret to High Performance (opens in new tab)

There is a point in every system’s growth where adding more servers stops being enough. You scale horizontally. You introduce load balancers. You distribute traffic efficiently. And yet, something still feels off. Requests are slower than expected. Databases are under constant pressure. Systems that should scale effortlessly begin to struggle under repeated work. And then you realise something fundamental: The system is doing the same work again and again. The same queries. The same computati...