I see, thanks.
I my own code I suspect that it's the for loops I can't vectorise that are making R taking so long in some operations, so this is where this project would help.
In R its very easy to simply create a function in C++ or Fortran, then call that. Plus there's plenty of functions already that you can call instead of using for loops in R (which really aren't idiomatic).
You can use python, call out to R libraries with Rpy2 and speed up loops to faster than Julia and around native Speed with numba