TitleEfficiently traverse repository hierarchy
Primary ActorRepository engineer
ScopeSystem (black-box)
LevelSummary
Story (A paragraph or two describing what happens)

Users should be able to quickly determine the set of ancestors which contain a given resource, or traverse the set of all children within a resource without the need for an external index.

This is complicated by the multiple approaches that can be used to represent hierarchy and directionality of containment/membership relations.