It’s easy to use and update the git version of Configgy and other code hosted at github. If you don’t have git, you can use MacPorts to install it:
$ sudo port install git
Then clone the Configgy repository with
$ git clone git://github.com/robey/configgy.git
Then cd into the top-level directory and build as described below.
When you want to update, just pull the latest changes and rebuild.
$ git pull
$ ant clean; ant package
Note that ant package may be particular to Configgy. Sometimes just ant is sufficient and will use the defaults.