I would be interested in your thoughts on using PochiVM as a means to add a dynamic re-compiling core for emulators. The emulator would identify hot code blocks, generate C like constructs (or ideally the AST) and use the 'Copy-and-Patch Compilation' algorithm to generate and execute the relevant machine code. The ability to call back to host methods, handle exception semantics and all the while being totally oblivious to the platform architecture that the machine code is produced for seems ideal for an emulator designed to run on multiple platforms.