System Design
Where your app's memory lives, and why this one choice shapes everything for years Every app remembers things: your account, your messages, your orders, your photos. All of that memory lives in a database. It is the most important box in almost every system diagram, and the choice
System Design
How a click crosses the world and comes back, and why "the app is slow" is usually a traffic problem When you tap a link, it feels instant. Behind that tap, your request finds an address, opens a connection, crosses the planet, gets handled, and comes all the
System Design
How software talks to software, from the first request to a payment that never double-charges Almost nothing you use is a single program. Your banking app is dozens of programs. So is your ride app, your email, the website you bought coffee filters from last night. They are built out