Media rights availability catalog
Design the media metadata + rights-availability catalog that decides, for every title in a streaming catalog, whether a given user in a given country can play it RIGHT NOW. Availability depends on licensing windows (a title is licensed in the US from June 1 to Sept 30, in Germany on different dates), device/platform rights, and content takedowns that must apply instantly worldwide. This catalog is read on every play attempt and every catalog browse for 250M users — extremely read-heavy with strict correctness (showing or playing an unlicensed title is a legal/contract breach).
Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.