How does it work?
Every time someone wants to extend the application, instead of modifying original `publishing.js` file, he or she can subscribe to given events, e.g.
Scenario: Table Of Contents extension
```
// resources/public/js/toc.js
events.subscribe('content:rendered', function () {
// Prepend table of contents in edit mode on updates
});
events.subscribe('document:loaded', function () {
// Prepend table of contents on initial load in edit view and preview
});
```
Now, having structured way to hook into app allows to keep the main codebase maintainable and pretty stable and extremely extensible at the same time.
Maciej Smolinski