I hadn't seen Phoenix before reading your comment, but I like the look of it. Looks useful for general compiler tinkering. When I looked at this a while back,

I hadn't seen Phoenix before reading your comment, but I like the look of it. Looks useful for general compiler tinkering. When I looked at this a while back, I was trying to do it in C# on Mono.Cecil. I got bogged down writing things like CSharpWhileLoopVisitor...