Cask is a Linux container system, like Docker and LXC. Cask creates lightweight isolated environments in which to run programs. Programs running in a container have their own isolated filesystem, network, etc. Cask containers are not VMs, though -- they share the host's kernel.
Under the hood, Cask works like Docker's native driver: by using clone() to create a new set of kernel namespaces.
Never use containers to run untrusted code! If you wouldn't run it on the host, don't run it in Cask.
Download the default image and import it:
$ cask image.import default https://ianpreston.io/cask/images/default.tar.gz
Create a new container called example from the default image and start it up:
$ cask create example default
$ cask start example
Open a shell inside the new container:
$ cask run example sh
First, install Cask's dependencies. On a recent Ubuntu, dependencies can be installed like so:
$ sudo apt-get install python2.7 python-setuptools build-essential curl
Clone the latest stable release of Cask:
$ git clone https://github.com/ianpreston/cask
$ cd cask
Build and install all of the components:
$ make
$ sudo make install
$ sudo make network