A harbor computes with cranes, tide charts, radios, customs windows, truck queues, and human patience. Every delay is a message moving through the system.
The temptation is to model everything. The better move is to model the few constraints that cause most of the waiting, then make them legible to the people who can act.
Infrastructure software works when it makes the physical world easier to coordinate, not when it hides the physical world behind a prettier abstraction.