So, now the inevitable question comes up again: Why use the OpenJDK downloaded/packaged by Oracle? I use Zulu builds [0] for everything, and the AdoptOpenJDK builds site has removed its not-for-production-use banner [1] (at least I don't see it anymore, not sure if intentional).
A number of companies will happily stand behind OpenJDK builds. I work for Pivotal, we build the JDKs and JREs that we ship to customers (and a lot of other languages too). Red Hat do too.
I'm the head Cat Herder (so to speak) for the AdoptOpenJDK OpenJDK binary build farm. The OpenJDK builds we are producing pass the regular OpenJDK tests, a series of system tests and the official TCK/JCK. The quality bar is high and once we've stabilised this process for Java 8,9,10, 11+ and all of the platforms (AIX, ARM 32/64, Windows, Mac, Linux, z390, zOS etc) then we'll be broadly advertising its service. Whether or not we earn the trust of enterprise, we'll have to see :-).
I also found: https://github.com/ojdkbuild/ojdkbuild while looking for Red Hat's build scripts. I didn't find those, but only because I am bad at searching. They'll be published somewhere.
The goal was to emulate what https://github.com/ojdkbuild/ojdkbuild started many years ago but take it alot further. Adopt will provide completely open transparent infrastructure as code (and infrastructure) for folks to build OpenJDK. We've got Red Hat, IBM, Oracle and SAP + various JUG's participating and I expect it'll become the common build farm for Java going forwards. People are also more than welcome to clone the whole thing and use it internally!
I'd try to find some friendly folks at Microsoft or Google -- I can imagine both being willing to donate some compute and storage, as they're looking for ways to attract Java workloads from AWS.
0 - https://www.azul.com/downloads/zulu/ 1 - https://adoptopenjdk.net/