Common code for all GUI stuff in FTB Mods. Component/layer based GUI creation. Used by mods such as FTB Chunks, FTB Quests, etc.

Example GUIs that are possible with it:

It also adds sidebar buttons that other mods can create with JSON files:

It's not meant to be depended on by non-FTB mods but it's not forbidden. If you lose your mind doing so, that's on you :p