>...unless they have reached a certain level of legend

That is a similar tactic I use now for anything core. I know I commented that we don't have any dependencies in our core systems, but as an afterthought, this isn't entirely accurate. We do, but as you said they are "legendary", and don't change a whole lot anymore.

I think you are on the right track. :)

Edit: Keep business practicality in mind, if using a 3rd party library means you feed your family or are productive for the business, you need to weigh these considerations carefully.

It's likely you need to use a dependency to get your work done, and then later when you are more profitable, you can clean it out if need be. Maybe that is how I should have worded my first comment in retrospect.