It persists data to disk in a manner that is easy to query. It allows observing changes to the data so that features update when necessary. It handles graphs of objects just fine thanks to recursive CTE's in SQLite. With a little bit of work it can handle historical edits with undo/redo. It seems to quack like Swift/Core Data to me, but bringing SQLite to the forefront instead of putting needless abstraction layers on top of it.