People who compile it themselves get no support whatsoever. Support is only available to verified buyers. See below on how to buy an official copy.
Download Links (SpigotMC):
- Plus version with tons of extra features and exclusive Discord support
- Free version that only gets bugfixes
- My other plugins
If you just need a working .jar file, buy AngelChest Plus on SpigotMC (link is above). If you have a legit reason to compile this yourself, join my Discord server and ask for help there (link is below).
TL;DR: You cannot simply run mvn package on this. And I won't help you how to do it. Buy the plugin on SpigotMC.
Information about the API can be found HERE