IFTTT-like Service API

I'm developing an app that amalgamates all of your notifications from various sources and presents them in an organized fashion. It's something like HomeKit, but not limited to only smart home-based notifications. Essentially it's a convenience app, and means that instead of having ten different apps that provide notifications, you have one app that centralizes the whole thing, ranging from HomeKit-like functionality, to telling you if you have a text message or email, to telling you if your favorite news source or twitter account posts something, to telling you if you've got something planned on your calendar, to even telling you if your home computer completed its backup successfully. So far, my first step is integrating IFTTT into it, e.g. something like notifying you if your house turns on its lights at sunset. However, while I found something called "Maker" on their website, it seems you have to create custom recipes in order to utilize it, and I would like it to be compatible with existing recipes. Is there any such SDK or API that will allow me to receive that information? Thank you in advance!

Side note: While yes, I realize that this is somewhat of a vague question, I could not think of an alternative forum to post this on, and if you have any suggestions for a more appropriate post location, I will gladly consider them.