Vagrant can be installed in Windows or Linux. The following is my development environment for the Vagrant CoreOS:
For a few of the examples in the book, I have used Vagrant to run CoreOS inside a Linux VM running on top of Windows laptop with Virtualbox.
git clone https://github.com/coreos/coreos-vagrant.git
config.rbfiles in the coreos-vagrant directory:
cd coreos-vagrant mv user-data.sample user-data ...