An introduction to the Julia language, part 1

Yes, if your calculation is such that you can take advantage of these libraries, you will get the performance of C or Fortran, with, for many routines, automatic parallelization. But, as I said in the article, "you can only take advantage of this if your calculation fits the pattern of an available routine". What Julia offers is fast performance not only for standard manipulations, such as matrix multiplication, but for calculations that do not fit one of these molds, for which you would need to write loops over arrays or other data structures.