Doesn't work with pytest-runner

I have the following setup.py file:

from setuptools import setup, find_packages

setup(
    name="mypkg",
    package_dir={'': 'src'},
    packages=find_packages('src'),
    version="0.1",
    install_requires=["pytest-xdist", "toolz>=0.7.4", "boto", "pyrfc3339", "pytz", "mock"],
    setup_requires=["pytest-runner"],
    dependency_links=[],
    include_package_data=True,
    zip_safe=False)

And the following package layout:

.
├── pytest.ini
├── setup.py
├── src
│   └── mypkg
└── tests
    ├── __init__.py
    └── test_misc.py

Using pytest-runner, this works fine:

python setup.py pytest

But if I add the -f switch to run with pytest-xdist, it fails on dependecy resolution:

python setup.py pytest --addopts=-f                                                                                               -- INSERT --
running pytest
Searching for mock
Best match: mock 1.3.0
Processing mock-1.3.0-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/mock-1.3.0-py2.7.egg
Searching for pytz
Best match: pytz 2015.7
Processing pytz-2015.7-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/pytz-2015.7-py2.7.egg
Searching for pyrfc3339
Best match: pyRFC3339 1.0
Processing pyRFC3339-1.0-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/pyRFC3339-1.0-py2.7.egg
Searching for boto
Best match: boto 2.39.0
Processing boto-2.39.0-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/boto-2.39.0-py2.7.egg
Searching for toolz>=0.7.4
Best match: toolz 0.7.4
Processing toolz-0.7.4-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/toolz-0.7.4-py2.7.egg
Searching for pytest-xdist
Best match: pytest-xdist 1.13.1
Processing pytest_xdist-1.13.1-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg
Searching for funcsigs
Best match: funcsigs 0.4
Processing funcsigs-0.4-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/funcsigs-0.4-py2.7.egg
Searching for six>=1.7
Best match: six 1.10.0
Processing six-1.10.0-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/six-1.10.0-py2.7.egg
Searching for pbr>=0.11
Best match: pbr 1.8.1
Processing pbr-1.8.1-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/pbr-1.8.1-py2.7.egg
Searching for py>=1.4.22
Best match: py 1.4.31
Processing py-1.4.31-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/py-1.4.31-py2.7.egg
Searching for pytest>=2.4.2
Best match: pytest 2.8.7
Processing pytest-2.8.7-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg
Searching for execnet>=1.1
Best match: execnet 1.4.1
Processing execnet-1.4.1-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg
Searching for apipkg>=1.4
Best match: apipkg 1.4
Processing apipkg-1.4-py2.7.egg

Using /Users/henriquealves/Code/nu/common-core-python/.eggs/apipkg-1.4-py2.7.egg
running egg_info
writing requirements to src/common_core_python.egg-info/requires.txt
writing src/common_core_python.egg-info/PKG-INFO
writing top-level names to src/common_core_python.egg-info/top_level.txt
writing dependency_links to src/common_core_python.egg-info/dependency_links.txt
reading manifest file 'src/common_core_python.egg-info/SOURCES.txt'
writing manifest file 'src/common_core_python.egg-info/SOURCES.txt'
running build_ext
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "<string>", line 3, in <module>
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg/execnet/__init__.py", line 9, in <module>
    import apipkg
ImportError: No module named apipkg
Traceback (most recent call last):
  File "setup.py", line 12, in <module>
    zip_safe=False)
  File "/Users/henriquealves/anaconda/envs/blank/lib/python2.7/distutils/core.py", line 151, in setup
    dist.run_commands()
  File "/Users/henriquealves/anaconda/envs/blank/lib/python2.7/distutils/dist.py", line 953, in run_commands
    self.run_command(cmd)
  File "/Users/henriquealves/anaconda/envs/blank/lib/python2.7/distutils/dist.py", line 972, in run_command
    cmd_obj.run()
  File "build/bdist.macosx-10.5-x86_64/egg/ptr.py", line 79, in run
  File "/Users/henriquealves/anaconda/envs/blank/lib/python2.7/site-packages/setuptools-19.4-py2.7.egg/setuptools/command/test.py", line 140, in with_project_on_sys_path
  File "build/bdist.macosx-10.5-x86_64/egg/ptr.py", line 124, in run_tests
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg/_pytest/config.py", line 48, in main
    return config.hook.pytest_cmdline_main(config=config)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg/_pytest/vendored_packages/pluggy.py", line 724, in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg/_pytest/vendored_packages/pluggy.py", line 338, in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg/_pytest/vendored_packages/pluggy.py", line 333, in <lambda>
    _MultiCall(methods, kwargs, hook.spec_opts).execute()
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest-2.8.7-py2.7.egg/_pytest/vendored_packages/pluggy.py", line 596, in execute
    res = hook_impl.function(*args)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg/xdist/looponfail.py", line 24, in pytest_cmdline_main
    looponfail_main(config)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg/xdist/looponfail.py", line 35, in looponfail_main
    remotecontrol.loop_once()
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg/xdist/looponfail.py", line 100, in loop_once
    self.setup()
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg/xdist/looponfail.py", line 64, in setup
    self.gateway = self.initgateway()
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/pytest_xdist-1.13.1-py2.7.egg/xdist/looponfail.py", line 56, in initgateway
    return execnet.makegateway("popen")
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg/execnet/multi.py", line 128, in makegateway
    gw = gateway_bootstrap.bootstrap(io, spec)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg/execnet/gateway_bootstrap.py", line 92, in bootstrap
    bootstrap_import(io, spec)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg/execnet/gateway_bootstrap.py", line 27, in bootstrap_import
    s = io.read(1)
  File "/Users/henriquealves/Code/nu/common-core-python/.eggs/execnet-1.4.1-py2.7.egg/execnet/gateway_base.py", line 389, in read
    "expected %d bytes, got %d" % (numbytes, len(buf)))
EOFError: expected 1 bytes, got 0

Here are the versions in .eggs:

README.txt          execnet-1.4.1-py2.7.egg     pbr-1.8.1-py2.7.egg     pytest-2.8.7-py2.7.egg      pytz-2015.7-py2.7.egg
apipkg-1.4-py2.7.egg        funcsigs-0.4-py2.7.egg      py-1.4.31-py2.7.egg     pytest_runner-2.6.2-py2.7.egg   six-1.10.0-py2.7.egg
boto-2.39.0-py2.7.egg       mock-1.3.0-py2.7.egg        pyRFC3339-1.0-py2.7.egg     pytest_xdist-1.13.1-py2.7.egg   toolz-0.7.4-py2.7.egg

Reproduce the failure from setup.py with python setup.py pytest --addopts=-f, then inspect pytest-xdist's looponfail.py entry points and the traceback through execnet. Confirm the dependency-resolution behavior around apipkg and verify that the command completes without the ImportError or EOFError.