I'm not sure if this is the appropriate forum to post this, so please accept my apologies if so. I have a slight suspicion that MacRuby is not working/not installed properly in my machine. In macirb, the class of an object is always reported as the Ruby class, not the NS class - e.g., string is always "String", when I believe it should be NSString. $ macirb irb(main):001:0> "foo".class => String also $ ruby -ve "p ''.methods.size" ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-darwin11.2.0] 162 $ macruby -ve "p ''.methods.size" MacRuby 0.10 (ruby 1.9.2) [universal-darwin10.0, x86_64] 162 when I would have expected the numbers to be higher in the second. Is this something that I should be concerned about? The curious thing is that I am working my way through Matt's book, and the examples seem to work properly (including in Xcode, apart from the hiccup with the recent 4.3 upgrade, which I haven't been able to resolve yet). Any help would be gratefully received. Thanks in advance. System is 10.7.3, Ruby 1.9.3, MacRuby 0.10, Xcode 4.3. Regards, Chong-Yee