Update (22 October): Things move very fast around here – the merb.thor file has been overhauled and now all you have to do to get the latest edge is download a single .thor file and run one command.
Matt Aimonetti wrote a neat post on installing merb edge with thor. Thor seems to have become the defacto technique for installing merb edge these days, and I’m going to give it a go in preference to installing merb with sake, as I had been doing.
Since Matt wrote his article the merb.thor file underwent a serious overhaul during the sprint at MerbCamp – what you need to do these days is quite a bit simpler:
curl -L http://merbivore.com/merb.thor > merb.thor
sudo thor merb:stack:install --edge
The source code for all the Merb gems will be checked out into a directory called ./src.
To get the full low down on how to use Thor with Merb, head over to the Thor Howto on the excellent new Merb wiki.