Another good Scheme implementation is [Chicken](http://www.call-cc.org). For our purposes, this is in some respects
superior to Racket, and in other respects inferior. If you have any issues with installing or using Racket, you could
try this out instead. You might even want to install both.
-
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-Racket doesn't have R7RS-small, and won't anytime soon.
+Racket doesn't have R7RS-small, and won't anytime soon. :-(
+Also Chicken's library collection seems stronger, or at least better organized and maintained.
Other R7RS-friendly: [Gauche](http://practical-scheme.net/gauche), [Chibi](https://code.google.com/p/chibi-scheme).
-->