I am writing another post which will describe better the niche I think it should fill - an auxiliary language used to write library modules which would be called from applications written in Elixir or Erlang.
The functionality that would be replaced is currently written by traversing lists - this really is a business-rules language add-on to existing infrastructure rather than a high-performance array processing language.
julia is rolling out an all-julia database solution, and I just wish they used BEAM (probably elixir) as supervisors on top of julia worker processes instead of relying on julia, principally because of the lack of reliability guarantees in julia (I love julia, but it's not really a programming language designed for that)
The functionality that would be replaced is currently written by traversing lists - this really is a business-rules language add-on to existing infrastructure rather than a high-performance array processing language.