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GitHub User: jamesfend
I spent about 6 hours stuck on getting Rmagick to work on OSX 10.6 and wanted to share my solution to maybe help at least somebody out there. Pretty much, I used homebrew to install Imagemagick but with a special way to avoid a bug I kept running into: http://stackoverflow.com/questions/2838307/why-is-this-rmagick-call-generating-a-segmentation-fault/8614289#8614289
(if you're using Macports, I feel sorry for you; definitely use Homebrew. Life is much, much easier)
Also then install the Rmagick gem. And things should be good to go.
Thanks Ryan for the great Railscasts as always.