sui is a no bullshit minecraft gui library for creating a lot of inventories in a short amount of time.
I've been looking for an inventory library that fits my needs for a long time, and there have been some things I loved in some libraries.
helper - This library is basically based on helper, because it's what I've been using the most.
canvas - This library has also inspired helper, but has some other cool features which I've drawn inspiration from.
ChickenPat - Big help with the default mask comparators