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GitHub User: JonnieCache
*>Is that comparable with awesome_nested_set?*
awesome_nested_set has been superseded by
a fork which has been renamed to just "nested_set" https://github.com/skyeagle/nested_set
Perhaps you have rspec included only in your test group, rather than in both the test and development groups in your gemfile, like in the 'cast.
any gems which have generators or command line tools of their own have to exist in the development environment as well so you can access them. otherwise you will get 'not found' errors.