> But it is nearly impossible to come up with an implementation for Ruby, that is as performant as a compiled C program

PyPy is getting there.

JIT, Runtime type detection and path optimization go a long way. And it's much easier to write correct Ruby than correct C.

When I went to college, the HP-41 was HP's top-of-the-line calculator and all the rich kids had them. I had a BASIC-programmable CASIO PB-700. In the end, I was able to finish tests in less time than it took the HP guys to program their calculators to spit the answer. I think it was the first time (1986 or so) I realized a more expressive programming language could be a decisive advantage over your competition.