Doma(in)Validity was born because I found myself searching online about how to check if a domain was valid. I always ended up using regular expressions that were too complex to account for several scenarios (mainly the TLD having different formats), it was just a pain in the butt because I always had to go back to that code to fix the regex to account for an edge case that I didn't think about.
Well, no more! Welcome Doma(in)Validity, this stupid simple API will check if a domain is valid or not based on the Public Suffix list.
I hope this is helpful for developers. You can see a working example here and a failing example here.