diff --git a/keyring/tests/util.py b/keyring/tests/util.py
index <HASH>..<HASH> 100644
--- a/keyring/tests/util.py
+++ b/keyring/tests/util.py
@@ -18,7 +18,7 @@ class ImportKiller(object):
         self.original = {}
         for name in self.names:
             self.original[name] = sys.modules.pop(name, None)
-        sys.meta_path.append(self)
+        sys.meta_path.insert(0, self)
     def __exit__(self, *args):
         sys.meta_path.remove(self)
         for key, value in self.original.items():
Fix ImportKiller not working with Python 3 (Fixes #<I>)

In Python 3, initial sys.meta_path is not empty, so custom importer modules
should be prepended, not appended.