To build an Allura vagrant box:

$ mkdir ~/vagrant_allura && cd ~/vagrant_allura

# Get the base box
$ vagrant box add ubuntu-1110-server-amd64 http://timhuegdon.com/vagrant-boxes/ubuntu-11.10.box
$ vagrant init

# Get a copy of the provisioning scripts
$ cp /var/local/allura/vagrant/* .

# At this point you can make whatever changes you want to the provisioning
# scripts

# Provision the box (this will take a while)
$ vagrant up

# Package the Allura box
$ vagrant package --vagrantfile Vagrantfile.pkg

# Test your new box
$ mkdir ~/vagrant_allura_test and cd ~/vagrant_allura_test
$ vagrant box add allura ~/vagrant_allura/package.box
$ vagrant init
$ vagrant ssh

# Do whatever testing you want...

# If everything checks out, you can rename your package.box and upload it