"Then someone wants regexps, or Windows path handling, or what-not" I think you would be hard pressed to find something that is available in Scheme but not C/C

"Then someone wants regexps, or Windows path handling, or what-not" I think you would be hard pressed to find something that is available in Scheme but not C/C++. Take regex, you have std::regex, many pcre wrappers and Google re2, which has strong linear time guarantee. If you go with chibi as recommended by the blog, does it come with a good regex binding? What if you want to use Google's library? By the time you figure out how to bind iterators or coroutines in c the effort may well have been used to roll your own c++ solution in the first place. "you didn't really implement Scheme macros" I agree that is a more serious barrier. One has to honestly assess one's own true understanding and ability in implementing the target language. I am not an expert in Scheme and I couldn't tell you how easy or hard this is. I did study Prolog and its implementations extensively so I knew exactly what I needed to do. There are so many good resources out there that if one is willling to put in the effort one will be richly rewarded for the learning experience.