I can definitely help you here! The code you write is yours to license as you please. So you can release the source for your game under GPLv3, you just can't distribute the engine alongside the source. Someone would have to own the engine and use your source alongside it to contribute to your game. You can compile and sell your game as you normally would, of course!

Here's an example of one of my games that is released under the Unlicense: https://github.com/brettchalupa/XENO.TEST & https://book.dragonriders.community/source-control.html#a-no... walks through how to do that

Zif is an open source community library for DragonRuby Game Toolkit that gives you a lot more classes and structure, if you so choose to use it. So it's not an "instead of" but rather a library you can drop into your DragonRuby Game Toolkit game.

While DragonRuby GTK is not FLOSS, your code is your code, and it's built upon mruby, llvm, and SDL, so it's got a really strong FLOSS core. I'm not a license expert tho, so maybe there are more implications than I'm realizing.

Thanks, Brett! Really appreciate the reply. I think tracking the 'mygame' directory is the way to go, and I'll also investigate packaging with Zif.