Note: This blog post is from 2020. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
This is a hidden gem that I never saw documented anywhere: CF2018 now imports environment variables into the CF "server" scope, specifically:
and java system properties into:
(Thanks to Sean C for catching a mistake in the initial post.)
I learned of it last year when Pete F tweeted about it, and I assumed someone else would do a post about it, but the topic came up in a discussion today and I was surprised to not be able to find any mention of it, other than that and his mention of it in his cfdocs.org site.
And yes, Lucee had it first (as proposed initially in 2015). :-)
The feature can be useful, whether you're setting such vars when running a (Docker) container, or via JVM args, etc., and you want to be able to access them within CFML.