It's a variable or config that gets injected into a server at runtime. At least that's what I've heard it called in the past. I think it's interchangeable with environment variable.

Maybe this is the part I misunderstood, what kind of "server" are we talking about? I understood it to mean "machine".

If they are trying to say "update application configuration" but wrote "update server variable", I urge them to revise their marketing ASAP.

Just updated the repo. Thanks for the clarification.

Yeah that's a good point. We meant application config. I will change the repo's description to reflect this.

So, configuration?