packagecloud.io missing curl error

Vagrantfile

# -*- mode: ruby -*-
# vi: set ft=ruby :

# Vagrantfile API/syntax version. Don't touch unless you know what you're doing!
VAGRANTFILE_API_VERSION = "2"

$script = <<SCRIPT
  wget https://packagecloud.io/install/repositories/basho/riak/script.deb -O /tmp/basho-repo.sh
  bash /tmp/basho-repo.sh
SCRIPT

Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|

  # Every Vagrant virtual environment requires a box to build off of.
  config.vm.box = "chef/ubuntu-12.04"

  config.vm.provision "shell", inline: $script

end