You must have a very peculiar understanding of how programming languages work. FWIW, there is no magic (of any color) in C++ or Julia. It’s just a compiler.
Idiomatic Julia code can generate programs that are as fast as optimized C or C++ (modulo some LLVM quirk). The great thing about Julia is that I can do this with relatively little effort, and still have maintainable code.
No, there is no need for this if you are coding in Julia.