C4 diagram example: microservices logistics platform

A single storefront is the easiest C4 example; a microservices platform with two dozen moving parts is the one people actually struggle to draw clearly. This example is a logistics platform with tracking, routing and carrier-integration services, a driver-facing app, and the external carriers it depends on — the same C4 discipline (Context → Container → Component) applied at a scale closer to a real system, with F4 flows showing how a parcel moves end to end.

At this size the value of drilling down instead of drawing one giant diagram becomes obvious: the System Context diagram stays readable with a handful of boxes, while the detail lives one click deeper, exactly where the reader who needs it will look for it.