diff --git a/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/BUCK b/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/BUCK
index 590d06c63c6..75b75835b3b 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/BUCK
+++ b/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/BUCK
@@ -29,6 +29,7 @@ rn_xplat_cxx_library(
         react_native_xplat_target("config:config"),
         react_native_xplat_target("fabric/uimanager:uimanager"),
         react_native_xplat_target("fabric/components/scrollview:scrollview"),
+        react_native_xplat_target("utils:utils"),
         react_native_target("jni/react/jni:jni"),
         "fbsource//xplat/fbsystrace:fbsystrace",
         "fbsource//xplat/folly:molly",
diff --git a/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp b/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp
index 3be8ba82e99..0fd303f2c82 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp
+++ b/ReactAndroid/src/main/java/com/facebook/react/fabric/jsi/jni/Binding.cpp
@@ -18,8 +18,8 @@
 #include <react/uimanager/ContextContainer.h>
 #include <react/uimanager/Scheduler.h>
 #include <react/uimanager/SchedulerDelegate.h>
-#include <react/uimanager/TimeUtils.h>
 #include <react/uimanager/primitives.h>
+#include <react/utils/TimeUtils.h>
 
 using namespace facebook::jni;
 using namespace facebook::jsi;
diff --git a/ReactCommon/fabric/mounting/BUCK b/ReactCommon/fabric/mounting/BUCK
index 674ad5b5611..23cf786a296 100644
--- a/ReactCommon/fabric/mounting/BUCK
+++ b/ReactCommon/fabric/mounting/BUCK
@@ -55,8 +55,11 @@ rn_xplat_cxx_library(
         "fbsource//xplat/folly:molly",
         "fbsource//xplat/third-party/glog:glog",
         react_native_xplat_target("better:better"),
+        react_native_xplat_target("fabric/components/root:root"),
+        react_native_xplat_target("fabric/components/view:view"),
         react_native_xplat_target("fabric/core:core"),
         react_native_xplat_target("fabric/debug:debug"),
+        react_native_xplat_target("utils:utils"),
     ],
 )
 
diff --git a/ReactCommon/fabric/uimanager/ShadowTree.cpp b/ReactCommon/fabric/mounting/ShadowTree.cpp
similarity index 98%
rename from ReactCommon/fabric/uimanager/ShadowTree.cpp
rename to ReactCommon/fabric/mounting/ShadowTree.cpp
index b008825bbf1..391471073a5 100644
--- a/ReactCommon/fabric/uimanager/ShadowTree.cpp
+++ b/ReactCommon/fabric/mounting/ShadowTree.cpp
@@ -11,7 +11,7 @@
 #include <react/debug/SystraceSection.h>
 #include <react/mounting/Differentiator.h>
 #include <react/mounting/ShadowViewMutation.h>
-#include <react/uimanager/TimeUtils.h>
+#include <react/utils/TimeUtils.h>
 
 #include "ShadowTreeDelegate.h"
 
@@ -96,6 +96,10 @@ ShadowTree::ShadowTree(
           /* .props = */ props,
           /* .eventEmitter = */ noopEventEmitter,
       }));
+
+#ifdef RN_SHADOW_TREE_INTROSPECTION
+  stubViewTree_ = stubViewTreeFromShadowNode(*rootShadowNode_);
+#endif
 }
 
 ShadowTree::~ShadowTree() {
diff --git a/ReactCommon/fabric/uimanager/ShadowTree.h b/ReactCommon/fabric/mounting/ShadowTree.h
similarity index 98%
rename from ReactCommon/fabric/uimanager/ShadowTree.h
rename to ReactCommon/fabric/mounting/ShadowTree.h
index 32811919764..09ca34f35cf 100644
--- a/ReactCommon/fabric/uimanager/ShadowTree.h
+++ b/ReactCommon/fabric/mounting/ShadowTree.h
@@ -13,8 +13,8 @@
 #include <react/core/LayoutConstraints.h>
 #include <react/core/ReactPrimitives.h>
 #include <react/core/ShadowNode.h>
+#include <react/mounting/ShadowTreeDelegate.h>
 #include <react/mounting/ShadowViewMutation.h>
-#include <react/uimanager/ShadowTreeDelegate.h>
 
 namespace facebook {
 namespace react {
diff --git a/ReactCommon/fabric/uimanager/ShadowTreeDelegate.h b/ReactCommon/fabric/mounting/ShadowTreeDelegate.h
similarity index 100%
rename from ReactCommon/fabric/uimanager/ShadowTreeDelegate.h
rename to ReactCommon/fabric/mounting/ShadowTreeDelegate.h
diff --git a/ReactCommon/fabric/uimanager/ShadowTreeRegistry.cpp b/ReactCommon/fabric/mounting/ShadowTreeRegistry.cpp
similarity index 100%
rename from ReactCommon/fabric/uimanager/ShadowTreeRegistry.cpp
rename to ReactCommon/fabric/mounting/ShadowTreeRegistry.cpp
diff --git a/ReactCommon/fabric/uimanager/ShadowTreeRegistry.h b/ReactCommon/fabric/mounting/ShadowTreeRegistry.h
similarity index 97%
rename from ReactCommon/fabric/uimanager/ShadowTreeRegistry.h
rename to ReactCommon/fabric/mounting/ShadowTreeRegistry.h
index 06549953c34..6f808d9aee1 100644
--- a/ReactCommon/fabric/uimanager/ShadowTreeRegistry.h
+++ b/ReactCommon/fabric/mounting/ShadowTreeRegistry.h
@@ -8,7 +8,7 @@
 #include <better/mutex.h>
 
 #include <react/core/ReactPrimitives.h>
-#include <react/uimanager/ShadowTree.h>
+#include <react/mounting/ShadowTree.h>
 
 namespace facebook {
 namespace react {
diff --git a/ReactCommon/fabric/uimanager/BUCK b/ReactCommon/fabric/uimanager/BUCK
index e92abaaa1c8..359f3b9e2b4 100644
--- a/ReactCommon/fabric/uimanager/BUCK
+++ b/ReactCommon/fabric/uimanager/BUCK
@@ -57,11 +57,11 @@ rn_xplat_cxx_library(
         "fbsource//xplat/jsi:jsi",
         "fbsource//xplat/third-party/glog:glog",
         react_native_xplat_target("config:config"),
-        react_native_xplat_target("fabric/components/root:root"),
         react_native_xplat_target("fabric/components/view:view"),
         react_native_xplat_target("fabric/mounting:mounting"),
         react_native_xplat_target("fabric/core:core"),
         react_native_xplat_target("fabric/debug:debug"),
+        react_native_xplat_target("utils:utils"),
     ],
 )
 
diff --git a/ReactCommon/fabric/uimanager/Scheduler.cpp b/ReactCommon/fabric/uimanager/Scheduler.cpp
index 37f2151cbcb..728bedcfa87 100644
--- a/ReactCommon/fabric/uimanager/Scheduler.cpp
+++ b/ReactCommon/fabric/uimanager/Scheduler.cpp
@@ -11,10 +11,10 @@
 #include <react/core/LayoutContext.h>
 #include <react/debug/SystraceSection.h>
 #include <react/uimanager/ComponentDescriptorRegistry.h>
-#include <react/uimanager/TimeUtils.h>
 #include <react/uimanager/UIManager.h>
 #include <react/uimanager/UIManagerBinding.h>
 #include <react/uimanager/UITemplateProcessor.h>
+#include <react/utils/TimeUtils.h>
 
 namespace facebook {
 namespace react {
diff --git a/ReactCommon/fabric/uimanager/Scheduler.h b/ReactCommon/fabric/uimanager/Scheduler.h
index 6bad79fc144..4426eda9a66 100644
--- a/ReactCommon/fabric/uimanager/Scheduler.h
+++ b/ReactCommon/fabric/uimanager/Scheduler.h
@@ -12,13 +12,13 @@
 #include <react/config/ReactNativeConfig.h>
 #include <react/core/ComponentDescriptor.h>
 #include <react/core/LayoutConstraints.h>
+#include <react/mounting/ShadowTree.h>
+#include <react/mounting/ShadowTreeDelegate.h>
+#include <react/mounting/ShadowTreeRegistry.h>
 #include <react/uimanager/ComponentDescriptorFactory.h>
 #include <react/uimanager/ComponentDescriptorRegistry.h>
 #include <react/uimanager/ContextContainer.h>
 #include <react/uimanager/SchedulerDelegate.h>
-#include <react/uimanager/ShadowTree.h>
-#include <react/uimanager/ShadowTreeDelegate.h>
-#include <react/uimanager/ShadowTreeRegistry.h>
 #include <react/uimanager/UIManagerBinding.h>
 #include <react/uimanager/UIManagerDelegate.h>
 #include <react/uimanager/primitives.h>
diff --git a/ReactCommon/fabric/uimanager/UIManager.cpp b/ReactCommon/fabric/uimanager/UIManager.cpp
index 6c6c9552dfd..dc2df34ab85 100644
--- a/ReactCommon/fabric/uimanager/UIManager.cpp
+++ b/ReactCommon/fabric/uimanager/UIManager.cpp
@@ -4,7 +4,7 @@
 
 #include <react/core/ShadowNodeFragment.h>
 #include <react/debug/SystraceSection.h>
-#include <react/uimanager/TimeUtils.h>
+#include <react/utils/TimeUtils.h>
 
 namespace facebook {
 namespace react {
diff --git a/ReactCommon/fabric/uimanager/UIManager.h b/ReactCommon/fabric/uimanager/UIManager.h
index 02fd1eda2f3..f8ccb65dd5b 100644
--- a/ReactCommon/fabric/uimanager/UIManager.h
+++ b/ReactCommon/fabric/uimanager/UIManager.h
@@ -8,8 +8,8 @@
 
 #include <react/core/ShadowNode.h>
 #include <react/core/StateData.h>
+#include <react/mounting/ShadowTreeRegistry.h>
 #include <react/uimanager/ComponentDescriptorRegistry.h>
-#include <react/uimanager/ShadowTreeRegistry.h>
 #include <react/uimanager/UIManagerDelegate.h>
 
 namespace facebook {
diff --git a/ReactCommon/fabric/uimanager/TimeUtils.h b/ReactCommon/utils/TimeUtils.h
similarity index 100%
rename from ReactCommon/fabric/uimanager/TimeUtils.h
rename to ReactCommon/utils/TimeUtils.h