A family of projects, including a universal IDE with plug-ins
for editing in different langauges (but not transformation plug-ins
that I'm aware of) and fine-grained source control, among others.
Website dedicated to something called program transformation.
Must investigate to determine what they mean by it.
Simon L. Peyton Jones.
Compiling Haskell by Program Transformation:
A Report from the Trenches,
European Symposium on Programming.
Appears to still use some hand coded front and back ends, but
takes goal of moving as much out of them as possible.
Getting Skinned: Swainess Flames,
Dr. Dobbs Journal.
Suggests text editors with 'plug in skins' for different types of text.
MDA from a Developer's Perspective,
Discusses "Model Driven Architechture," which uses UML modeling tools
and hand coded (if "scriptable") output generators.