diff --git a/cibuildwheel/linux.py b/cibuildwheel/linux.py
index dc7238a6..20dae7e6 100644
--- a/cibuildwheel/linux.py
+++ b/cibuildwheel/linux.py
@@ -145,6 +145,8 @@ def build(project_dir, output_dir, test_command, test_requires, test_extras, bef
                     venv_dir=`mktemp -d`/venv
                     python -m virtualenv "$venv_dir"
 
+                    export __CIBW_VIRTUALENV_PATH__=$venv_dir
+
                     # run the tests in a subshell to keep that `activate`
                     # script from polluting the env
                     (
diff --git a/cibuildwheel/macos.py b/cibuildwheel/macos.py
index dd2a412b..3b3edcba 100644
--- a/cibuildwheel/macos.py
+++ b/cibuildwheel/macos.py
@@ -209,6 +209,7 @@ def build(project_dir, output_dir, test_command, test_requires, test_extras, bef
                 os.path.join(venv_dir, 'bin'),
                 virtualenv_env['PATH'],
             ])
+            virtualenv_env["__CIBW_VIRTUALENV_PATH__"] = venv_dir
 
             # check that we are using the Python from the virtual environment
             call(['which', 'python'], env=virtualenv_env)
diff --git a/cibuildwheel/windows.py b/cibuildwheel/windows.py
index 59f67460..24e19c38 100644
--- a/cibuildwheel/windows.py
+++ b/cibuildwheel/windows.py
@@ -179,10 +179,16 @@ def build(project_dir, output_dir, test_command, test_requires, test_extras, bef
             shell(['python', '-m', 'virtualenv', venv_dir], env=env)
 
             virtualenv_env = env.copy()
+
+            venv_script_path = os.path.join(venv_dir, 'Scripts')
+            if os.path.exists(os.path.join(venv_dir, 'bin')):
+                # pypy2.7 bugfix
+                venv_script_path = os.pathsep.join([venv_script_path, os.path.join(venv_dir, 'bin')])
             virtualenv_env['PATH'] = os.pathsep.join([
-                os.path.join(venv_dir, 'Scripts'),
+                venv_script_path,
                 virtualenv_env['PATH'],
             ])
+            virtualenv_env["__CIBW_VIRTUALENV_PATH__"] = venv_dir
 
             # check that we are using the Python from the virtual environment
             shell(['which', 'python'], env=virtualenv_env)
diff --git a/test/02_test/test/spam_test.py b/test/02_test/test/spam_test.py
index faf7e6bc..ba5f5e91 100644
--- a/test/02_test/test/spam_test.py
+++ b/test/02_test/test/spam_test.py
@@ -1,9 +1,45 @@
+from __future__ import print_function
+import os
+import sys
 from unittest import TestCase
 
 import spam
 
 
+def path_contains(parent, child):
+    ''' returns True if `child` is inside `parent`.
+
+    Works around path-comparison bugs caused by short-paths on Windows e.g.
+    vssadm~1 instead of vssadministrator
+    '''
+    parent = os.path.abspath(parent)
+    child = os.path.abspath(child)
+
+    while child != os.path.dirname(child):
+        child = os.path.dirname(child)
+        if os.stat(parent) == os.stat(child):
+            # parent and child refer to the same directory on the filesystem
+            return True
+    return False
+
+
 class TestSpam(TestCase):
     def test_system(self):
         self.assertEqual(0, spam.system('python -c "exit(0)"'))
         self.assertNotEqual(0, spam.system('python -c "exit(1)"'))
+
+    def test_virtualenv(self):
+        virtualenv_path = os.environ.get("__CIBW_VIRTUALENV_PATH__")
+        if not virtualenv_path:
+            self.fail("No virtualenv path defined in environment variable __CIBW_VIRTUALENV_PATH__")
+
+        print("=[executable]", sys.executable)
+        print("=[spam location]", spam.__file__)
+        print("=[virtualenv path]", virtualenv_path)
+        print("=[listdir]", os.listdir(virtualenv_path))
+        if os.path.exists(os.path.join(virtualenv_path, 'Scripts')):
+            print("=[listdir]2", os.listdir(os.path.join(virtualenv_path, 'Scripts')))
+        if os.path.exists(os.path.join(virtualenv_path, 'bin')):
+            print("=[listdir]2", os.listdir(os.path.join(virtualenv_path, 'bin')))
+        self.assertTrue(path_contains(virtualenv_path, sys.executable))
+        self.assertTrue(path_contains(virtualenv_path, spam.__file__))