Design

This tier records why the rib is built the way it is. A change that trips over one of these decisions should argue with the record, not around it.

DecisionsThe shape of the problem, and the decisions the rib rests on.

GuardrailsWhat a bus does not give you for free, and what the rib adds.

DeferredWhat the rib does not do yet, and what each item is waiting on.