Marionette is a composite application library for Backbone.js that aims to simplify the construction of large scale JavaScript applications. It is a collection
"Marionette made a significant jump. The first implementation for version 3.3.1 was about 248% slower than the then fastest pure javascript ‘vanillajs’ version. Version 4.0.0-beta.1 is only 24% slower than domc." - stefankrause.net/wp/?p=504