Personally, I think free software are really important, and I love the developers that I am hiring to be in this mindset as well.
So the first think I am doing is to check their gitlab / github profiles. If they love to write code and to share it, there obviously will be code there to check.
Of course this code could be written with help of an AI but, nothing is preventing the developer to use it while working as well. As long as the result if good, everything is fine.