I'd be curious to hear how you'd do the execution flow like they mention? Just use multiple sequential slides?

I'm not sure if this is considered animation or not, but I've demonstrated code refactors between slides by adding a colored border around the code in question (both in the before and in the after slide).

I'd probably do something similar for stepping through code. But at that point it's a quasi-animation (albeit, one that can still be understood by pdf slides).