Neophyte here. I'm guessing that the root of the failure is 'rake' is accessing ruby 1.8 files versus 1.9, even though I have ruby 1.9 as my default: [/Users/Ric/workarea/svn/MacRuby/trunk]ruby --version ruby 1.9.1p0 (2009-01-30 revision 21907) [i386-darwin9] Here's the abridged rake run: [/Users/Ric/workarea/svn/MacRuby/trunk]sudo rake --trace Password: (in /Users/Ric/workarea/svn/MacRuby/trunk) ** Invoke default (first_time) ** Invoke all (first_time) ** Invoke macruby (first_time) ** Invoke macruby:build (first_time) ** Invoke macruby:dylib (first_time) ** Invoke rbconfig (first_time) ** Invoke miniruby (first_time) ** Invoke objects (first_time) ** Invoke config_h (first_time) ** Execute config_h ** Invoke dtrace_h (first_time) ** Execute dtrace_h ** Invoke revision_h (first_time) ** Execute revision_h ** Execute objects /usr/bin/ruby tool/compile_prelude.rb prelude.rb miniprelude.c.new rm miniprelude.c.new /usr/bin/ruby -Ks tool/insns2vm.rb opt_sc.inc optinsn.inc optunifs.inc insns.inc insns_info.inc vmtc.inc vm.inc /Users/Ric/workarea/svn/MacRuby/trunk/tool/instruction.rb:7:in `<top (required)>': RubyVM is not a module (TypeError) from tool/insns2vm.rb:7:in `require' from tool/insns2vm.rb:7:in `<main>' rake aborted! Command failed with status (1): [/usr/bin/ruby -Ks tool/insns2vm.rb opt_sc....] /Library/Ruby/Gems/1.8/gems/rake-0.8.4/lib/rake.rb:969:in `sh' /Library/Ruby/Gems/1.8/gems/rake-0.8.4/lib/rake.rb:982:in `call' /Library/Ruby/Gems/1.8/gems/rake-0.8.4/lib/rake.rb:982:in `sh' /Library/Ruby/Gems/1.8/gems/rake-0.8.4/lib/rake.rb:1070:in `sh' /Users/Ric/workarea/svn/MacRuby/trunk/Rakefile:337 ... Any clues as to what is happening? Ric.