[wheybags]

To me, the best case scenario is adding a dependency of medium size and complexity that you're confident you could write yourself. This means that if you run into problems, you can just shrug, and then ditch the library, but if it's ok then you save some time. What's terrifying is dependencies so large that you can't fathom the amount of effort required to make them. It also makes it much harder to tell if the library is actually any good. Luckily for your example of time libraries there's normally a "blessed" library for whatever ecosystem you're in. Tiny / super simple dependencies are a complete waste of time, if I can write it in < 1hr I would much prefer to do so.

IMO there's a lot to be said for writing your own version that does 60% of what some library does, but 100% of what you need it to do.