You can’t have everything at once — not in a treehouse, not in a school timetable, and not in the software running your favourite apps. This guide explains architectural trade-offs — what they really are, why they’re unavoidable, the five building-block words (quality attribute, scenario, sensitivity point, trade-off point, risk),…
Faster, cheaper, simpler, safer, and able to handle a million users — every team wants all five. This guide explains the honest reason no system ever gets all five at maximum strength: shared limited resources, mathematically opposite goals, and the weight every extra feature adds. Plus a look at the…
Whenever a computer system is split across many machines, it runs into a moment where it must choose between two good things and can’t have both. This guide unpacks the CAP theorem — what its three letters really stand for, why the trade-off is unavoidable, how CP and AP systems…
Every big app you use is built like a building — and just like buildings, software can be put together in very different ways. This guide walks through the main architectural styles engineers choose from — layered, client-server, microservices, event-driven, microkernel, SOA, plus pipe-and-filter, peer-to-peer, master-slave, space-based, serverless, and broker…
Think of your favourite layer cake — sponge, then cream, then fruit, each layer sitting neatly on the one below it. Software can be built the very same way. This guide unpacks layered architecture from the ground up — the classic layers (presentation, business, persistence, data), how a request travels…
Every time you open an app and something appears on your screen a moment later, two very different computers just had a quiet conversation. This guide explains client-server architecture from the ground up — the two roles and the shared protocol between them, the four steps behind every request, the…
A doorbell doesn’t know who is about to answer it, and it doesn’t need to. It just rings the moment something happens, and lets whoever is listening decide what to do next. This guide explains event-driven architecture from the ground up — its four building blocks, how a single event…
A kitchen works best when the chef cooks, the cashier takes payments, and the cleaner keeps things tidy — each person doing one job well, instead of everyone trying to do everything at once. Software works the very same way. This guide unpacks separation of concerns — its history, the…
Two puppets tied together by the very same string move only when the puppeteer allows it — pull one, and the other jerks along whether it wanted to or not. Software has strings just like this. This guide explains coupling from the ground up — its six main types, the…
A drawer full of nothing but forks feels obvious the moment you open it. A drawer full of forks, batteries, rubber bands, and an old birthday candle does not. This guide unpacks cohesion — the quiet quality that decides whether a piece of software behaves like the first drawer or…