Ribbit's max library contains most of the R4RS predefined procedures (even call/cc). The main things missing are variadic procedures (unfortunately this includes the "list" procedure so you need to replace (list 1 2 3) by (cons 1 (cons 2 (cons 3 '())))) and also all the file opening operations. There is read-char, write-char, etc but they only do console I/O. These things could be added at the price of a larger footprint. One simple way to do this is to have the RVM run the code of a meta-circular Scheme evaluator written in Scheme.

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Thanks. I will check it out.