diff --git a/app.yaml b/app.yaml
index 5716a17..b6f0141 100644
--- a/app.yaml
+++ b/app.yaml
@@ -6,22 +6,27 @@ handlers:
 
 - url: /bower_components
   static_dir: bower_components
+  secure: always
 
 - url: /data
   static_dir: data
+  secure: always
 
 - url: /images
   static_dir: images
+  secure: always
 
 - url: /(.*).(html|js|json|css)
   static_files: \1.\2
   upload: (.*)\.(html|js|json|css)
+  secure: always
 
 - url: /$
   static_files: index.html
   upload: index\.html
-  #http_headers:
-  #  Access-Control-Allow-Origin: "*"
+  http_headers:
+    Link: '</elements/elements.js>; rel=preload; as=script, </scripts/bundle.js>; rel=preload; as=script, </styles/app.css>; rel=preload; as=style'
+    # Access-Control-Allow-Origin: "*"
   secure: always
 
 skip_files: