diff --git a/pypiserver/__init__.py b/pypiserver/__init__.py
index 85df9a8..0a4806c 100644
--- a/pypiserver/__init__.py
+++ b/pypiserver/__init__.py
@@ -4,16 +4,27 @@ version = __version__ = "0.5.2"
 
 def app(root=None,
         redirect_to_fallback=True,
-        fallback_url="http://pypi.python.org/simple"):
+        fallback_url=None):
     import os
     from pypiserver import core
     import bottle
 
     if root is None:
         root = os.path.expanduser("~/packages")
+
+    if fallback_url is None:
+        fallback_url="http://pypi.python.org/simple"
+
     os.listdir(root)
     core.packages = core.pkgset(root)
     core.config.redirect_to_fallback = redirect_to_fallback
     core.config.fallback_url = fallback_url
     bottle.debug(True)
     return bottle.default_app()
+
+
+def paste_app_factory(global_config, **local_conf):
+    root = local_conf.get("root")
+    redirect_to_fallback = local_conf.get("redirect_to_fallback", "").lower() in ("yes", "on", "1")
+    fallback_url = local_conf.get("fallback_url")
+    return app(root=root, redirect_to_fallback=redirect_to_fallback, fallback_url=fallback_url)