So after trying a couple of things back and forth I decided that my blueprint for coding challenges should have been a Maven archetype. Which was really hard to achieve, and I had worked with archetypes in the past.
But now it’s done, I have two projects in Maven Central, which feels kinda nice.
(Also, yes that GUI is incredible ugly. But there is no supported GUI framework in Java any longer, so you can pry Swing from my cold dead hands.)