Update (20 Mar 2017): That something is C. I’ve been using C and bash scripting for the last year and a half, and it does this all.
and the most important thing of all:
I am looking for a single solution that will handle these things. MATLAB almost has it, but they are holding on too tightly to their monolithic nature as the be-all, end-all of scientific computing. They need to be humble enough, when appropriate, to become just a tool in bigger toolchains.