Interesting. I feel silly that it never occurred to me to pop the hood to see how AdoptOpenJDK was doing things and it strikes me as pretty solid.

For comparsion, here's the repo where we keep our builder for OpenJDK: https://github.com/cloudfoundry/java-buildpack-dependency-bu...

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.