Not sure what you mean here but OS projects that come to mind that we haven't treated as a black-box at some point are kubernetes, docker, node, chromium, rabbitmq, postgres and every JavaScript module we use.
Two local services that come to mind that we have used and that didn't work like the AWS equivalent is dynalite and fake-s3.
I mean have you actually inspected the source code and/or made changes to suit your needs for infrastructure level resources where there is a managed equivalent?
