[curun1r]

I think they made a mistake by making the "gets configuration parameters from the environment" specific to a UNIX/system environment. You can accomplish the same effect in a much more elegant manner using a tool like etcd or consul.

But the important part is really that the deployable unit pulls its configuration from the environment where it's deployed. There are a ton of ways to accomplish this...environment variables are one way, etcd/consul is another, you can use something language-specific like JNDI or you can even use a file with configs in a well-known location, but you really need to be deploying the same artifact to QA, E2E testing, production and whatever other environments you might have.