I think the name mruby kind of makes sense; we have MRI (matz ruby implementation) so the leading "M" there; we have jruby too. We also have truffleruby which is a bit against that name scheme ... but we could call it truby. Nobody does that, but we could. And MRI could also be called c-ruby. These are not great names though. Murby is also not a great name; it reminds me of Murphy from Robocop though.