I'm wondering if it's even possible to integrate this with Drush Make. RIght now, for example, you can add this to a .make file:

api = 2
core = 7.x

projects[composer] = 1.x-dev
projects[] = composer_autoload
projects[] = guzzle

And it says it works, and you can enable the guzzle without any errors, but the Guzzle class isn't actually installed so you can't do anything with it.

So I'm wondering if it's even possible to make this stuff with from within a drush make file or if that's just a pipe dream?