What is the purpose if /Libraries/ folder? In this folder sub-folders you should put all your 3rd party code packages, and in the /Libraries/ folder you should put transpilers from 3rd Party libraries to your Plugin code. This is important to do, so that you can standardize the calls of your 3rd party methods in your code. ------------------------------------------------------------------------ What is transpiler? Transpiler - It's a source-to-source compiler, it translates source code from one language to another (or to another version of the same language). Note: Library transpiler class should not have a namespace, because all transpilers are loaded as dynamic libraries and that would anyway require a full-qualified namespaces for each transpiler constructor. So to avoid that, we just do not use namespaces for transpilers at all.