vagrant up docker fails

[samuell]

[samuel devbox-golang]$ vagrant up docker
Identity added: keys/vagrantssh.key (keys/vagrantssh.key)
Bringing machine 'docker' up with 'virtualbox' provider...
There are errors in the configuration of this machine. Please fix
the following errors and try again:

vm:
* A box must be specified.

[samuell]

This issue seems to be spot on ... looking into it.