diff --git a/packages/metro-config/package.json b/packages/metro-config/package.json
index b8703bd178db..e4a834061e09 100644
--- a/packages/metro-config/package.json
+++ b/packages/metro-config/package.json
@@ -20,7 +20,8 @@
   },
   "exports": {
     ".": "./src/index.js",
-    "./package.json": "./package.json"
+    "./package.json": "./package.json",
+    "./src/internalCallsites": "./src/internalCallsites.js"
   },
   "publishConfig": {
     "exports": {
diff --git a/packages/metro-config/src/index.flow.js b/packages/metro-config/src/index.flow.js
index 5fb4be2cd3fe..e4c54ec2ab39 100644
--- a/packages/metro-config/src/index.flow.js
+++ b/packages/metro-config/src/index.flow.js
@@ -10,32 +10,13 @@
 
 import type {ConfigT, InputConfigT} from 'metro-config';
 
+import {INTERNAL_CALLSITES_PATTERNS} from './internalCallsites';
 import {getDefaultConfig as getBaseConfig, mergeConfig} from 'metro-config';
 
 export type {MetroConfig} from 'metro-config';
 
 const INTERNAL_CALLSITES_REGEX = new RegExp(
-  [
-    '/Libraries/BatchedBridge/MessageQueue\\.js$',
-    '/Libraries/Core/.+\\.js$',
-    '/Libraries/LogBox/.+\\.js$',
-    '/Libraries/Network/.+\\.js$',
-    '/Libraries/Pressability/.+\\.js$',
-    '/Libraries/Renderer/implementations/.+\\.js$',
-    '/Libraries/Utilities/.+\\.js$',
-    '/Libraries/vendor/.+\\.js$',
-    '/Libraries/WebSocket/.+\\.js$',
-    '/src/private/renderer/errorhandling/.+\\.js$',
-    '/metro-runtime/.+\\.js$',
-    '/node_modules/@babel/runtime/.+\\.js$',
-    '/node_modules/@react-native/js-polyfills/.+\\.js$',
-    '/node_modules/invariant/.+\\.js$',
-    '/node_modules/react-devtools-core/.+\\.js$',
-    '/node_modules/react-native/index.js$',
-    '/node_modules/react-refresh/.+\\.js$',
-    '/node_modules/scheduler/.+\\.js$',
-    '^\\[native code\\]$',
-  ]
+  INTERNAL_CALLSITES_PATTERNS
     // Make patterns work with both Windows and POSIX paths.
     .map(pathPattern => pathPattern.replaceAll('/', '[/\\\\]'))
     .join('|'),
diff --git a/packages/metro-config/src/internalCallsites.js b/packages/metro-config/src/internalCallsites.js
new file mode 100644
index 000000000000..6e496e58835c
--- /dev/null
+++ b/packages/metro-config/src/internalCallsites.js
@@ -0,0 +1,45 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+'use strict';
+
+/**
+ * Path suffixes identifying stack frames from React Native internals. Used
+ * to collapse internal callsites in the symbolicator and to detect
+ * third-party modules in the serializer.
+ *
+ * Plain JavaScript with no dependencies: this module is also required
+ * directly (bypassing `src/index.js`) from runtimes without the monorepo
+ * toolchain, like the Buck worker zip, where `scripts/shared/babelRegister`
+ * cannot be resolved and Flow syntax cannot be parsed.
+ */
+const INTERNAL_CALLSITES_PATTERNS = [
+  '/react-native/Libraries/BatchedBridge/MessageQueue\\.js$',
+  '/react-native/Libraries/Core/.+\\.js$',
+  '/react-native/Libraries/LogBox/.+\\.js$',
+  '/react-native/Libraries/Network/.+\\.js$',
+  '/react-native/Libraries/Pressability/.+\\.js$',
+  '/react-native/Libraries/Renderer/implementations/.+\\.js$',
+  '/react-native/Libraries/Utilities/.+\\.js$',
+  '/react-native/Libraries/vendor/.+\\.js$',
+  '/react-native/Libraries/WebSocket/.+\\.js$',
+  '/react-native/src/private/renderer/errorhandling/.+\\.js$',
+  '/metro-runtime/.+\\.js$',
+  '/node_modules/@babel/runtime/.+\\.js$',
+  '/node_modules/@react-native/js-polyfills/.+\\.js$',
+  '/node_modules/invariant/.+\\.js$',
+  '/node_modules/react-devtools-core/.+\\.js$',
+  '/node_modules/react-native/index.js$',
+  '/node_modules/react-refresh/.+\\.js$',
+  '/node_modules/scheduler/.+\\.js$',
+  '^\\[native code\\]$',
+];
+
+module.exports = {INTERNAL_CALLSITES_PATTERNS};