diff --git a/cibuildwheel/macos.py b/cibuildwheel/macos.py
index 1344c9ff..3bd0df79 100644
--- a/cibuildwheel/macos.py
+++ b/cibuildwheel/macos.py
@@ -92,7 +92,7 @@ def build(project_dir, output_dir, test_command, test_requires, test_extras, bef
         call(['python', '--version'], env=env)
 
         # install pip & wheel
-        call(['python', get_pip_script, '--no-setuptools', '--no-wheel'], env=env)
+        call(['python', get_pip_script, '--no-setuptools', '--no-wheel'], env=env, cwd="/tmp")
         assert os.path.exists(os.path.join(installation_bin_path, 'pip'))
         call(['pip', '--version'], env=env)
         call(['pip', 'install', '--upgrade', 'setuptools', 'wheel', 'delocate'], env=env)
diff --git a/cibuildwheel/windows.py b/cibuildwheel/windows.py
index e5d3240d..7c03f815 100644
--- a/cibuildwheel/windows.py
+++ b/cibuildwheel/windows.py
@@ -124,7 +124,7 @@ def build(project_dir, output_dir, test_command, test_requires, test_extras, bef
 
         # make sure pip is installed
         if not os.path.exists(os.path.join(config_python_path, 'Scripts', 'pip.exe')):
-            simple_shell(['python', get_pip_script], env=env)
+            simple_shell(['python', get_pip_script], env=env, cwd="C:\\cibw")
         assert os.path.exists(os.path.join(config_python_path, 'Scripts', 'pip.exe'))
 
         # prepare the Python environment
diff --git a/test/09_setup_cfg/cibuildwheel_test.py b/test/09_setup_cfg/cibuildwheel_test.py
new file mode 100644
index 00000000..9e9ffce6
--- /dev/null
+++ b/test/09_setup_cfg/cibuildwheel_test.py
@@ -0,0 +1,13 @@
+import os
+import utils
+
+
+project_dir = os.path.dirname(__file__)
+
+def test():
+    # build the wheels
+    actual_wheels = utils.cibuildwheel_run(project_dir)
+
+    # check that the expected wheels are produced
+    expected_wheels = utils.expected_wheels('spam', '0.1.0')
+    assert set(actual_wheels) == set(expected_wheels)
diff --git a/test/09_setup_cfg/setup.cfg b/test/09_setup_cfg/setup.cfg
new file mode 100644
index 00000000..b42c221a
--- /dev/null
+++ b/test/09_setup_cfg/setup.cfg
@@ -0,0 +1,6 @@
+[metadata]
+name = spam
+version = attr: spam.__version__
+
+[options]
+packages = find:
\ No newline at end of file
diff --git a/test/09_setup_cfg/setup.py b/test/09_setup_cfg/setup.py
new file mode 100644
index 00000000..0fbbe75e
--- /dev/null
+++ b/test/09_setup_cfg/setup.py
@@ -0,0 +1,8 @@
+import os
+
+from setuptools import setup, Extension
+
+
+setup(
+    ext_modules=[Extension('spam.spam', sources=['spam/spam.c'])],
+)
diff --git a/test/09_setup_cfg/spam/__init__.py b/test/09_setup_cfg/spam/__init__.py
new file mode 100644
index 00000000..a68927d6
--- /dev/null
+++ b/test/09_setup_cfg/spam/__init__.py
@@ -0,0 +1 @@
+__version__ = "0.1.0"
\ No newline at end of file
diff --git a/test/09_setup_cfg/spam/spam.c b/test/09_setup_cfg/spam/spam.c
new file mode 100644
index 00000000..d1ab0f22
--- /dev/null
+++ b/test/09_setup_cfg/spam/spam.c
@@ -0,0 +1,48 @@
+#include <Python.h>
+
+static PyObject *
+spam_system(PyObject *self, PyObject *args)
+{
+    const char *command;
+    int sts;
+
+    if (!PyArg_ParseTuple(args, "s", &command))
+        return NULL;
+    sts = system(command);
+    return PyLong_FromLong(sts);
+}
+
+/* Module initialization */
+
+#if PY_MAJOR_VERSION >= 3
+    #define MOD_INIT(name) PyMODINIT_FUNC PyInit_##name(void)
+    #define MOD_DEF(m, name, doc, methods, module_state_size) \
+        static struct PyModuleDef moduledef = { \
+            PyModuleDef_HEAD_INIT, name, doc, module_state_size, methods, }; \
+        m = PyModule_Create(&moduledef);
+    #define MOD_RETURN(m) return m;
+#else
+    #define MOD_INIT(name) PyMODINIT_FUNC init##name(void)
+    #define MOD_DEF(m, name, doc, methods, module_state_size) \
+        m = Py_InitModule3(name, methods, doc);
+    #define MOD_RETURN(m) return;
+#endif
+
+static PyMethodDef module_methods[] = {
+    {"system", (PyCFunction)spam_system, METH_VARARGS, 
+     "Execute a shell command."},
+    {NULL}  /* Sentinel */
+};
+
+MOD_INIT(spam)
+{
+    PyObject* m;
+
+    MOD_DEF(m, 
+            "spam", 
+            "Example module", 
+            module_methods,
+            -1)
+
+    MOD_RETURN(m)
+}