diff --git a/microsite/sidebars.json b/microsite/sidebars.json
index e76faac0ed..d52c00b3da 100644
--- a/microsite/sidebars.json
+++ b/microsite/sidebars.json
@@ -416,6 +416,14 @@
           "frontend-system/building-plugins/extension-types"
         ]
       },
+      {
+        "type": "category",
+        "label": "Building Apps",
+        "items": [
+          "frontend-system/building-apps/index",
+          "frontend-system/building-apps/built-in-extensions"
+        ]
+      },
       {
         "type": "category",
         "label": "Utility APIs",