The new reference manual for version 0.2 (which I'll release within a few days) discusses Bevy specifically. Short version: GameLisp isn't a natural fit for a multithreaded ECS, but it's possible to make it work.

Because the language is so dynamic and late-bound, it shouldn't be too difficult to hack in hotloading yourself. I intend to make it easier in the future. There's some preliminary discussion here:

https://github.com/fleabitdev/glsp/issues/10