Yeah. It‘s the framework which does pretty much all of the interesting technical work, if I may say so. It does the communication with other phones and determines if there was a contact and generates, stores and maintains the tokens and given the server data figures out matches and so on. It has a tiny, simple to use API on top.

It was jointly developed by Apple and Google. For free.

That's what I thought, it seems that the entire project is basically a fancy wrapper around the Exposure Notification apis provided by Apple and Google.

There's some kind of cognitive dissonance around your idea that these companies deserve so much compensation for designing a solution that relies so heavily (entirely) on these features, and yet be free from responsibility for serious bugs that arise from this decision.