How much of the FogBugz code had to be modified to accommodate static typing, even with global type inference? In other words, was there much code that truly depended on dynamic typing? My guess is that Joel and his team were more disciplined about this than I've been. (Yes, I'm entertaining the idea of writing a custom compiler from a dynamically typed language, in my case Lua, to a statically typed one, probably C++ with heavy use of reference counting.)