I cannot edit my comment, but you're completely right about it being optimised. I will say that I'm not familiar with what idioms might the Mojo compiler be able to optimise better (a problem arising with the Mojo compiler still being closed source, in comparison with the open source nature of Julia), and, in this sense, I don't know if there is more "compiler friendly" code with the same semantics for Mojo that might allow it to get nearer to Julia results.