diff --git a/package.json b/package.json
index 6021173..8bf1e34 100644
--- a/package.json
+++ b/package.json
@@ -111,5 +111,8 @@
       "babel-runtime": "npm:babel-runtime@^5.8.24",
       "core-js": "npm:core-js@^1.1.4"
     }
-  }
+  },
+  "cacheDirectories": [
+    "node_modules", "web/public/jspm_packages"
+  ]
 }