Here is my main gripe with Julia: They blatantly copy Matlab. The same is also true to a lesser degree of Python's numpy and matplotlib, but Julia goes the whole nine yards, by basically replicating the syntax and copying most of the numerical APIs including the indexing convention. I understand why they do it and I get that Matlab is hugely popular, I just wish that there was more creative energy in the Open Source world and not just rehashing of 20-40 year old designs.