WordPress is a fantastic system in many ways, but one place that it’s really lacking is the ability to extend existing plug-ins. There is no built-in system of dependency when it comes to WordPress plug-ins, unfortunately.
Therefore, if you’re thinking of adding on to an existing WordPress plug-in, you basically have two options:
- You can modify the plug-in itself
Using this method isn’t all that ideal, because any changes you make will obviously be overwritten whenever the plug-in is updated.
- You can write a plug-in that attempts to depend on the other plug-in
With this method, if something changes in the other plug-in that causes your dependency check to fail, you could end up breaking the WordPress installation (which results in a blank white screen on most installations)