From 589db9ebf0dbcbd74d089ff52dec9480f4fd4439 Mon Sep 17 00:00:00 2001
From: Antonis Lilis <antonis.lilis@sentry.io>
Date: Tue, 19 May 2026 15:05:29 +0200
Subject: [PATCH 1/2] fix(core): Preserve Metro config object identity in
 serializer wrapper

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .../src/js/tools/sentryOptionsSerializer.ts   | 16 ++++---
 .../tools/sentryOptionsSerializer.test.ts     | 47 +++++++++++++++++++
 2 files changed, 56 insertions(+), 7 deletions(-)

diff --git a/packages/core/src/js/tools/sentryOptionsSerializer.ts b/packages/core/src/js/tools/sentryOptionsSerializer.ts
index f30b144394..d9aa62c35a 100644
--- a/packages/core/src/js/tools/sentryOptionsSerializer.ts
+++ b/packages/core/src/js/tools/sentryOptionsSerializer.ts
@@ -57,13 +57,15 @@ export function withSentryOptionsFromFile(config: MetroConfig, optionsFile: stri
     return originalSerializer(entryPoint, preModules, graph, options);
   };
 
-  return {
-    ...config,
-    serializer: {
-      ...config.serializer,
-      customSerializer: sentryOptionsSerializer,
-    },
-  };
+  // Preserve Expo's __originalSerializer marker so Expo can detect user-provided serializers
+  if ('__originalSerializer' in originalSerializer) {
+    Object.assign(sentryOptionsSerializer, {
+      __originalSerializer: (originalSerializer as Record<string, unknown>).__originalSerializer,
+    });
+  }
+
+  config.serializer.customSerializer = sentryOptionsSerializer;
+  return config;
 }
 
 function createSentryOptionsModule(filePath: string): Module<VirtualJSOutput> | null {
diff --git a/packages/core/test/tools/sentryOptionsSerializer.test.ts b/packages/core/test/tools/sentryOptionsSerializer.test.ts
index 8027ff1953..f558e05618 100644
--- a/packages/core/test/tools/sentryOptionsSerializer.test.ts
+++ b/packages/core/test/tools/sentryOptionsSerializer.test.ts
@@ -165,6 +165,53 @@ describe('Sentry Options Serializer', () => {
     expect(actualResult).toEqual(mockedResult);
   });
 
+  test('mutates config in place to preserve object identity for Expo serializer closures', () => {
+    const config = {
+      projectRoot: '/test',
+      serializer: {
+        customSerializer: customSerializerMock,
+        getModulesRunBeforeMainModule: jest.fn(),
+      },
+    };
+    const originalSerializerObj = config.serializer;
+
+    const result = withSentryOptionsFromFile(config, true);
+
+    expect(result).toBe(config);
+    expect(result.serializer).toBe(originalSerializerObj);
+    expect(result.serializer?.customSerializer).not.toBe(customSerializerMock);
+    expect(result.serializer?.getModulesRunBeforeMainModule).toBe(config.serializer.getModulesRunBeforeMainModule);
+  });
+
+  test('preserves __originalSerializer marker from Expo serializer', () => {
+    const expoSerializer = Object.assign(jest.fn(), { __originalSerializer: null });
+    const config = {
+      projectRoot: '/test',
+      serializer: {
+        customSerializer: expoSerializer,
+      },
+    };
+
+    const result = withSentryOptionsFromFile(config, true);
+
+    expect('__originalSerializer' in (result.serializer?.customSerializer as Record<string, unknown>)).toBe(true);
+    expect((result.serializer?.customSerializer as Record<string, unknown>).__originalSerializer).toBeNull();
+  });
+
+  test('does not add __originalSerializer when original serializer lacks it', () => {
+    const plainSerializer = jest.fn();
+    const config = {
+      projectRoot: '/test',
+      serializer: {
+        customSerializer: plainSerializer,
+      },
+    };
+
+    const result = withSentryOptionsFromFile(config, true);
+
+    expect('__originalSerializer' in (result.serializer?.customSerializer as Record<string, unknown>)).toBe(false);
+  });
+
   test('uses custom file path when optionsFile is a string', () => {
     const config = () => ({
       projectRoot: '/test',

From be48b926f10c972c4334baf1330d5a3c8daf79e5 Mon Sep 17 00:00:00 2001
From: Antonis Lilis <antonis.lilis@sentry.io>
Date: Tue, 19 May 2026 15:06:20 +0200
Subject: [PATCH 2/2] docs(changelog): Add changelog entry for #6188

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cb3e7e49d0..583e2c6c3a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -25,6 +25,7 @@
 - Fix boolean options from `sentry.options.json` being ignored on Android when using `RNSentrySDK.init` ([#6130](https://github.com/getsentry/sentry-react-native/pull/6130))
 - Fix `includeWebFeedback: false` Metro config option causing crash at startup ([#6150](https://github.com/getsentry/sentry-react-native/pull/6150))
 - Fix `sentry-expo-upload-sourcemaps` failing for projects with `devEngines.packageManager` set to non-npm managers ([#6155](https://github.com/getsentry/sentry-react-native/pull/6155))
+- Fix Metro serializer wrapper breaking `getModulesRunBeforeMainModule` for third-party plugins like `react-native-worklets` `bundleMode` ([#6188](https://github.com/getsentry/sentry-react-native/pull/6188))
 
 ### Dependencies