Access to Rev User Interface Controls

[Mikey]

Yes.  The fact that the IDE is bootstrapped is wonderful, because so
much in RR is hackable.  I've written several hacks to date to add
features that I could have waited years for otherwise.

It is a nice balance - the engine is compiled and out of the way, but
the rest is interpreted so I don't have to edit, compile, debug,
repeat before getting something useful.  In addition, the interpreted
nature means that it is trivial to drop in, read, debug, tweak, and
get out.  This is much better than doing it in many other tools that
are just built for raw speed and to hide the details from you at the
expense of being able to have the freedom to have at it.