Provision a virtual machine for building ChromeOS using Vagrant <http://www.vagrantup.com>. Just download this into a directory, name it ``Vagrantfile`` (if it isn't already), run ``vagrant up`` followed by ``vagrant ssh`` and you'll see two shell scripts there, ready to sync up the ChromeOS source code.

Vagrantfile

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

Vagrant.configure("2") do |config|
  # All Vagrant configuration is done here. The most common configuration
  # options are documented and commented below. For a complete reference,
  # please see the online documentation at vagrantup.com.

  # Every Vagrant virtual environment requires a box to build off of.
  config.vm.box = "ubuntu1204_64"

  # The url from where the 'config.vm.box' box will be fetched if it
  # doesn't already exist on the user's system.
  config.vm.box_url = "http://cloud-images.ubuntu.com/precise/current/precise-server-cloudimg-vagrant-amd64-disk1.box"

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine. In the example below,
  # accessing "localhost:8080" will access port 80 on the guest machine.
  # config.vm.network :forwarded_port, guest: 80, host: 8080

  # Create a private network, which allows host-only access to the machine
  # using a specific IP.
  # config.vm.network :private_network, ip: "192.168.33.10"

  # Create a public network, which generally matched to bridged network.
  # Bridged networks make the machine appear as another physical device on
  # your network.
  config.vm.network :public_network

  # If true, then any SSH connections made will enable agent forwarding.
  # Default value: false
  # config.ssh.forward_agent = true

  # Share an additional folder to the guest VM. The first argument is
  # the path on the host to the actual folder. The second argument is
  # the path on the guest to mount the folder. And the optional third
  # argument is a set of non-required options.
  # config.vm.synced_folder "../data", "/vagrant_data"

  # Provider-specific configuration so you can fine-tune various
  # backing providers for Vagrant. These expose provider-specific options.
  # Example for VirtualBox:
  #
  config.vm.provider :virtualbox do |vb|
    vb.gui = true
    ## four cpus seems like a reasonable guess in modern times
    vb.customize ["modifyvm", :id, "--memory", "8192", "--cpus", "4"]
  end

  # everything you see here came from the Pre-req section of the dev guide:
  # http://dev.chromium.org/chromium-os/developer-guide#TOC-Prerequisites
  $prov_git = <<PROV_GIT
set -e
set -x
## Vagrant runs this script as root, so be aware
echo "=== HELLO FROM $0 ==="
if test "$USER" == "root"
then
  su - vagrant -c "$0"
  exit 0
fi

echo '=== USER INFO ==='
id -a

if test -d chromiumos
then
  echo "You already have a chromiumos directory, which I will not modify." >&2
  exit 0
fi

echo '=== INSTALL GIT ==='
sudo apt-get install -y git-core subversion curl

echo '=== INSTALL DEPOT TOOLS ==='
cd $HOME
git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
## http://dev.chromium.org/developers/how-tos/install-depot-tools specifically
## says to put depot_tools at the end of the path
echo "PATH=\$PATH:\$HOME/depot_tools" >> $HOME/.bashrc

echo '=== FIX UP SUDO ==='
##http://www.chromium.org/tips-and-tricks-for-chromium-os-developers#TOC-Making-sudo-a-little-more-permissive
cat<<SUDO1 | sudo tee /etc/sudoers.d/relax_requirements
Defaults !tty_tickets # Entering your password in one shell affects all shells 
Defaults timestamp_timeout=180 # Minutes between re-requesting your password
SUDO1
sudo chmod 0440 /etc/sudoers.d/relax_requirements

echo '=== GENERATE CHROMIUM SSH KEY ==='
ssh-keygen -t rsa -b 1024 -C "$USER@$HOSTNAME" -f $HOME/.ssh/chromium -N ''

echo '=== INSTALL KEYCHAIN ==='
## TODO: is it better to follow their order, so folks know what's going on
##       or better to batch up the apt-get instructions? 
sudo apt-get install -y keychain 

echo '=== FIX UMASK ==='
echo 'umask 022' >> $HOME/.bashrc

echo '=== CREATE ChromiumOS DIR ==='
mkdir -p $HOME/chromiumos

echo '=== GERRIT KNOWN HOSTS ==='
cat >> $HOME/.ssh/known_hosts<<SSH1
[gerrit.chromium.org]:29418 ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQCfRn+J+e9mU0c4bxFD8v2rhhd3O9WPk435xEtG9FD8a8fOnIubJcpObvQJhfSgYkxVUQOKk97V8b2eGjf72AGBhDQVJMiaLQc8ZGomeNlK/7cWjkJFDoIKQHilHQidz/pgZc/Pu+7Tl2emVGd6425QRK1h47CYtT9IUPt3Jtdv4w==
SSH1

echo '=== REPO CLONE SCRIPTS ==='
## now it's their turn:
cat > repo_sync_mini.sh<<REPO1
#! /bin/sh
cd ${HOME}/chromiumos 
repo init -u https://git.chromium.org/git/chromiumos/manifest.git -g minilayout --repo-url https://git.chromium.org/git/external/repo.git
repo sync
REPO1
chmod a+x repo_sync_mini.sh

cat > repo_sync_full.sh<<REPO2
#! /bin/sh
cd ${HOME}/chromiumos 
repo init -u https://git.chromium.org/git/chromiumos/manifest.git --repo-url https://git.chromium.org/git/external/repo.git
repo sync
REPO2
chmod a+x repo_sync_full.sh

echo '=== HAPPY HACKING TO YOU ==='

PROV_GIT
  config.vm.provision :shell, :inline => $prov_git
end

Is it not the same as https://github.com/bacongobbler/chromeos-vagrant?