Given the requirements I was rooting for Guile. He ended up choosing TinyScheme. Those who have not kept up with Guile development for the last 4 years would, I think, would be very pleasantly surprised, I was.<p>It has been vigorously developed upon, lots of changes to make it more performant and you can catch the highlights of all this action on Andy Wingo's blog <a href="http://wingolog.org/tags/guile" rel="nofollow">http://wingolog.org/tags/guile</a><p>I like his rundown of different Scheme implementations <a href="http://wingolog.org/archives/2013/01/07/an-opinionated-guide-to-scheme-implementations" rel="nofollow">http://wingolog.org/archives/2013/01/07/an-opinionated-guide...</a> including the comments that readers left there.<p>Another neat scheme for games that I am aware of is ypsilon <a href="http://code.google.com/p/ypsilon/" rel="nofollow">http://code.google.com/p/ypsilon/</a> one driving motivation for it was to keep GC pauses small, pretty important for games. I believe it has an incremental GC, not a fully concurrent one.<p>> The requirements included "Windows (compiled with MSCV) and iOS." Guile can do that?<p>Yep! with MinGW on Windows. IIRC they distribute such a prepackaged bundle. Will probably work with cygwin dlls too. Dont know about GUI inter-op, but Guile would build with Xcode<p>@xpolitix Good point about the need to link statically on iOS, had not thought about that one.