Switching between several Rails versions
Original: FiveRuns Blog. What worked for me:$ cd /opt && git clone git://github.com/rails/rails.git $ cd /opt/rails $ git tag # list of possible versions $ git checkout v1.2.6 $ ruby ./railties/bin/rails ~/Work/my126app $ rsync --exclude=.git -a . /home/ruby18/my126app/vendor/rails3 months ago