[saidajigumi]

From my own experience with Ruby and MRI, there's quite a strong culture of "transparency of code". It's not unusual if you're really down into some "interesting" problem to delve first into your gems/frameworks, and eventually even into MRI itself. Being a PL polyglot pays off in spades in these cases, since you get a solid understanding of the underpinnings of everything.

Note that there's very rarely any need to go there, but the fact that it's both possible and culturally encouraged makes a huge difference for those of us who've needed it.