I don't think the style described in that doc is at all ugly. It's practical and simple. I say this as someone who spends a lot of time writing modern c++ and h

I don't think the style described in that doc is at all ugly. It's practical and simple. I say this as someone who spends a lot of time writing modern c++ and heavily using templates. I thoroughly enjoy rust, but I doubt not being able to use it should be grounds for avoiding contributing to a project. Unless you are going to write async heavy code, libusb is pretty easy to use in C.