What good would it do for AWS to send it’s changes upstream? No one else could use it without the rest of AWS’s infrastructure.

We're at a point in time where f(x) = y and we're starting to stop caring about the internals of "f" as long as the "determinism is equivalent" and that scares me.

OpenJDK for example and the API/ABI (whatever you want to call it) copyright and now MongoDB with DocumentDB, etc.

We’ve been at that point since the first PC compatibles came out in the mid 80s with clean room reverse engineered BIOS firmware.

We’ve been living with abstractions over the underlying infrastructure for over 45 years.

Do you know how your CPU works? Or all the networking hardware in the middle of you loading this page? There are 1000s of layers when it comes to computing that it’s impossible to be transparent with them all.

And quite frankly, that end functionality is what customers are paying for, so that they don’t have to care about all the technical details and operational overhead. It's not like open-source Postgres is being halted by this. The Citus extension itself is open-source too.