[nohat]

The power of allowing everyone to make foundational types and functions that work together is indeed dangerous. I'm not sure you are better off in the even more dangerous waters of c/c++/fortran, except that they are older and more established with many times the man-hours sunk into them. Is there a good way to control the interaction of these many different libraries with losing the generality and composability of Julia?

I will say that as a matter of language design 1 based indexing is perfectly fine, 0 based indexing is perfectly fine. Choose your own indexing is a hilarious foot gun, so no surprise it went off sometimes. Fortunately using it seems to be quite rare.

[DNF2]

But it's not a matter of language design. The 'choose your own indexing' is something you do entirely in libraries.

You can create your own indexing in python too, it will just be slow. The 'sin' of Julia is that it will be fast...