> OffsetArrays in particular proved to be a strong source of correctness bugs. The package provides an array type that leverages Julia’s flexible custom indices feature to create arrays whose indices don’t have to start at zero or one.
I always thought this sounded like a bad idea. I remember one time I was working with a C++ guy on a Matlab project, and he handed me some Matlab code with 0 based indexing assumed. I said "Did you even run this code?", and he assured me he had. But of course he had not, because if he did it would have complained about the 0-based indices. But the point is that it did complain when I ran it, and I was able to match it to my code. I imagine in Julia he would have used 0-based indices, and I would have used 1-based, and our programs would have silently failed.