So I know for installation, generally you need to run composer global require "fxp/composer-asset-plugin:1.0.0-beta4" before you create the project with composer. However I was following the instructions for working directly in vagrant, which went swimmingly until I loaded up the backend and tried to generate the docs. running ./yii app/setup-docs throws:
[InvalidArgumentException]
No driver found to handle Asset VCS repository http://omnipotent.net/jquery.sparkline/2.1.2/jquery.sparkline.min.js
I'm not exactly sure if the composer asset plugin was supposed to be incorporated in the vagrant file somehow, or if it needed to be run manually?
To give an answer which might also help other people using Yii 2.0, Vagrant or Docker, I need to point out a few things.
The error occurs, because of the missing asset plugin on your host machine, there are several open issues (as of Jan'15) about this behavior, see #3607 and #3082.
But it is a feature of Phundament to provide a fully-set up development environment, with all plugins and packages pre-installed (but also updatable) and working. Therefore, when you run commands or scripts within a container or VM, they'll work (fingers-crossed).
As pointed out in a comment above, running composer in a VM or container is usually slower than on your host machine.
So as a summary: If you have your development (host-)machine set up correctly you may run composer there. If you're unsure use the container.
Full disclosure: I am the author of Phundament.