The Charming Ruby Compiler is charming not just by name, but by nature. It's a thesis project at the Computer Science Department at Chalmers University of Technology in Sweden to develop a proof of concept Ruby compiler that compiles to the C-- intermediate language. So far, they've only got the basics working, but it's an interesting project, if only to learn about C--, an interesting 'portable assembly language' that makes life easier for compiler developers. It seems a little like Parrot, and is funded by Microsoft Research and the National Science Foundation.
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References:https://www.sapphiresteel.com/Products/Ruby-In-Steel/Ruby-In-Steel-Developer-Overview