The Defeatureify project is no longer maintained.
broccoli-defeatureify 
Remove specially flagged feature blocks and debug statements using Defeatureify
Defeatureify is used in the ember-dev package to enable or remove features and strip debug statements during the Ember.js build process.
Issues with the output should be reported on the Defeatureify issue tracker.
$ npm install --save-dev broccoli-defeatureify
const Defeatureify = require('broccoli-defeatureify');
tree = new Defeatureify(tree, options);See the Defeatureify options.
MIT © Sindre Sorhus
