diff --git a/CHANGELOG.md b/CHANGELOG.md
index 82e52d44d3..75d4c36f01 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.28.6 - 2018-11-05
+## Fixed
+- `Dash.registered_paths` changed to a `collections.defaultdict(set)`, was appending the same package paths on every index. [#443](https://github.com/plotly/dash/pull/443)
+
 ## 0.28.5 - 2018-10-18
 ## Fixed
 - Replace windows endline when generating the components classes docstring [#431](https://github.com/plotly/dash/pull/431)
diff --git a/dash/dash.py b/dash/dash.py
index 0a68d70bce..2311571eab 100644
--- a/dash/dash.py
+++ b/dash/dash.py
@@ -167,7 +167,7 @@ def _handle_error(error):
 
         self.assets_ignore = assets_ignore
 
-        self.registered_paths = {}
+        self.registered_paths = collections.defaultdict(set)
 
         # urls
         self.routes = []
@@ -313,10 +313,7 @@ def _collect_and_register_resources(self, resources):
         def _relative_url_path(relative_package_path='', namespace=''):
 
             # track the registered packages
-            if namespace in self.registered_paths:
-                self.registered_paths[namespace].append(relative_package_path)
-            else:
-                self.registered_paths[namespace] = [relative_package_path]
+            self.registered_paths[namespace].add(relative_package_path)
 
             module_path = os.path.join(
                 os.path.dirname(sys.modules[namespace].__file__),
diff --git a/dash/version.py b/dash/version.py
index 1364a70d22..b0897f0bfd 100644
--- a/dash/version.py
+++ b/dash/version.py
@@ -1 +1 @@
-__version__ = '0.28.5'
+__version__ = '0.28.6'