People also use PHP to write backend scripts, without web use at all.
While the original and primary purpose may have been for personal home pages, it has evolved considerably since then. Consider an accounting/aggregate billing script for a PHP application that runs on a scheduler. That isn't dependent on the web necessarily, but it does interface with the moving parts of the overall application. Async would be great here.
Man, I remember thinking that Elixir was going to take the world by storm about 5 years ago. I was so excited for it. I hope it does though, it has a lot of great things going for it, and I'd love to see it adopted.
It's pretty practical so far. Right now I'm just finishing up chapter 4 (HTTP Servers, Routing, and Middleware), so I haven't completed all of it. But as it stands, a lot of what you go through, you reasonably expect you may be able to use on an actual pen test. The real power though, is when you're building out your own tooling with these things.
You just set up a framework in the book, but this is all easily extendable to whatever you want. I'm not the best at Go, so it's a useful "nightly devotion" of time to spend working through it for an hour or so.
I've also been going through Writing an Interpreter in Go, and have picked up the companion to that Writing a Compiler in Go. So far, that's pretty good too, but I'm focusing on Black Hat Go first, to complete it.
While the original and primary purpose may have been for personal home pages, it has evolved considerably since then. Consider an accounting/aggregate billing script for a PHP application that runs on a scheduler. That isn't dependent on the web necessarily, but it does interface with the moving parts of the overall application. Async would be great here.