An attempt to explicitly installs package dependencies **before** running `setuptools.setup`…

setup.py

from pip.commands import install
from pip.exceptions import DistributionNotFound


def setup2(**kwargs):
    kwargs['install_requires'] = kwargs.get('dependency_links', []) + kwargs.get('install_requires', [])

    if path.exists('requirements.txt'):
        kwargs['install_requires'] += open('requirements.txt', 'r').readlines()

    install_cmd = install.InstallCommand()

    print 'Installing:', kwargs['install_requires']
    try:
        install_cmd.run(*install_cmd.parse_args(kwargs['install_requires']))
    except DistributionNotFound as e:
        name = e.message[e.message.rfind(' ') + 1:]
        if len(filter(lambda n: n == name, kwargs['install_requires'])) > 1:
            pass
        else:
            print e
            kwargs['install_requires'] = filter(lambda i: i != name,
                                                kwargs['install_requires']) # HAAAACK
            # raise e  # RAISE THIS!
    kwargs.pop('install_requires')  # Deps already handled [hopefully!]
    return setup(**kwargs)

Hacked this together whilst troubleshooting: http://stackoverflow.com/q/28540839