I have used Nbdev and I am not a fan. It creates friction when one wants to contribute (in my case, to fast.ai) and forces you to write your code with notebooks which is the point but also not great when you are writing code rather than producing a display mixing text and pictures. Plus, while notebooks should favour documentation in theory, you can also end up with notebooks full of blob of code with transitions text that does not help you undertsanding what's going on.

Case in point, here is a random notebook from the fastai repository, a python file would be simpler to read and shorter: https://github.com/fastai/fastai/blob/master/nbs/09b_vision....