No, here's where he plays with JavaScript: http://cs.stanford.edu/people/karpathy/convnetjs/

This is "on web where all books should be" and claims to "contain very little math" despite being nothing but an endless list of formulae and absurd javascript math that looks like it was ripped out of a BASIC language manual for "how to draw circles" in text mode circa 1978.

Nothing wrong with JavaScript. And maybe this prof is working out some issues his students are struggling with.

But this ain't exactly the Feynman lectures:

    var x_try = x + tweak_amount * (Math.random() * 2 - 1); // tweak x a bit
    var y_try = y + tweak_amount * (Math.random() * 2 - 1); // tweak y a bit