I didn't see this mentioned, and I'm not a part of the Discord (is there even one?), but can premade code assets one has previously made (not necessarily third party) be used? Things such as character controllers, audio systems, state machines, controller input, scene management, etc. Or does that all count as part of the "code" which needs to be built from scratch?
Just curious since a good practice when it comes to building games is learning to build reusable code bases to speed up development.