[Darkness Falls: They mostly come out at night...]

Excuse me, I just read the intro to your addon and it sounds like you've achieved something I'm looking to do in one of my own:

 

I've also tried to inject a little realism by locking away quite a few recipes behind perks, since most normal folks wouldn't know how to do/make those things.

 

I asked about similar, if not exactly that, here and was pointed in the right direction. I'm pretty sure I found what I need but I was hoping to check in with you to learn exactly how you locked schematics behind perk requirements (eg: You need perks x & y in order to read and understand schematic z).