--- a/foodtruck/views/preview.py	Sat Apr 16 23:12:06 2016 -0700
+++ b/foodtruck/views/preview.py	Wed Apr 20 23:07:27 2016 -0700
@@ -2,6 +2,7 @@
 from flask import g, make_response
 from flask.ext.login import login_required
 from piecrust import CACHE_DIR
+from piecrust.app import PieCrustFactory
 from piecrust.serving.server import Server
 from ..web import app
 
@@ -16,10 +17,12 @@
 @login_required
 def preview_site(sitename, url):
     root_dir = g.sites.get_root_dir(sitename)
-    sub_cache_dir = os.path.join(root_dir, CACHE_DIR, 'foodtruck')
-    server = Server(root_dir, sub_cache_dir=sub_cache_dir,
-                    root_url='/site/%s/' % sitename,
-                    debug=app.debug)
+    appfactory = PieCrustFactory(
+            root_dir,
+            cache_key='foodtruck',
+            debug=app.debug)
+    server = Server(appfactory,
+                    root_url='/site/%s/' % sitename)
     return make_response(server._run_request)