Inverted Ownership, Part 2 - Wide Awake Developers

My last post on the subject of inverted ownership felt a bit abstract, so I thought I might illustrate it with a typical scenario. In this first figure, we see a newly-extracted Catalog service, freshly factored out of the old monolithic application. It's part of the company's effort to become more maneuverable. We don't know, or particularly care, what storage model it uses internally. From the outside, it presents an interface that looks like "