For over two years now Microsoft has been working in near-complete silence and secrecy, with only the occasional blip of publicity, on a new compiler technology.

Described in various places as a “compiler-as-a-service” system, and codenamed “Roslyn,” the new technology purports to be nothing less than an inside-out rewrite of the way Microsoft’s Visual Basic and C# compilers work.

Hints about Roslyn emerged back in 2011, when it was revealed that information generated about the program by the compiler can in turn be re-used by the program itself. This allows the programmer much deeper access than before into how their own programs work when compiled, and would even permit things like dynamic variable typing. (C# and Visual Basic are statically typed languages.)

The demonstration back then included such eye-opening possibilities as converting a Visual Basic program to C# (and back), but was still considered a highly experimental technology. Consequently, no time frame was given for when Roslyn’s technology would be made part of Microsoft’s Visual Studio product family.

Then a long silence descended upon the project, punctuated only by a Community Technology Preview (CTP) for the project in September 2012.

Just this week, new word about the project emerged by way of a blog post at MSDN.com, “Throwing the Big Switch on Roslyn,” in which Matt Gertz, Visual Studios managed languages development manager, talks at length about what Roslyn is, where it stands, and what it’s intended to do.