From 4351f855e06613e80d5a5e33d7e93d5fc5e6b41f Mon Sep 17 00:00:00 2001
From: "sentry-junior[bot]"
 <264270552+sentry-junior[bot]@users.noreply.github.com>
Date: Mon, 19 Oct 2026 14:06:59 +0000
Subject: [PATCH] fix(v10/astro): defer to `@sentry/cloudflare/vite` on
 Cloudflare Workers
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Backport of: #25347

Co-Authored-By: Jan VamPeer Stöcklmair <jan.peer@sentry.io>
---
 .../astro-6-cf-workers/astro.config.mjs       | 11 +++
 .../astro-6-cf-workers/instrument.server.js   |  9 ++
 .../sentry.server.config.js                   | 13 ---
 .../worker-configuration.d.ts                 |  2 +-
 .../astro-6-cf-workers/wrangler.jsonc         |  2 +-
 .../.gitignore                                |  4 -
 .../instrument.server.ts                      | 10 ---
 .../package.json                              | 29 ------
 .../playwright.config.ts                      | 12 ---
 .../start-event-proxy.mjs                     |  6 --
 .../tests/package-entry.test.ts               | 32 -------
 .../vite.config.ts                            | 15 ----
 .../worker-entry/fetch-handler.js             | 11 ---
 .../worker-entry/package.json                 |  9 --
 .../wrangler.jsonc                            |  8 --
 packages/astro/src/integration/cloudflare.ts  | 10 ++-
 packages/astro/src/integration/index.ts       | 35 +++++++-
 .../integration/cloudflareVitePlugin.test.ts  | 48 ++++++++++
 packages/astro/test/integration/index.test.ts | 89 +++++++++++++++++++
 19 files changed, 198 insertions(+), 157 deletions(-)
 create mode 100644 dev-packages/e2e-tests/test-applications/astro-6-cf-workers/instrument.server.js
 delete mode 100644 dev-packages/e2e-tests/test-applications/astro-6-cf-workers/sentry.server.config.js
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/.gitignore
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/instrument.server.ts
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/package.json
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/playwright.config.ts
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/start-event-proxy.mjs
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/tests/package-entry.test.ts
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/vite.config.ts
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/fetch-handler.js
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/package.json
 delete mode 100644 dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/wrangler.jsonc
 create mode 100644 packages/astro/test/integration/cloudflareVitePlugin.test.ts

diff --git a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/astro.config.mjs b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/astro.config.mjs
index f19212596282..5eef35199932 100644
--- a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/astro.config.mjs
+++ b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/astro.config.mjs
@@ -2,6 +2,7 @@ import sentry from '@sentry/astro';
 // @ts-check
 import { defineConfig } from 'astro/config';
 import cloudflare from '@astrojs/cloudflare';
+import { sentryCloudflareVitePlugin } from '@sentry/cloudflare/vite';
 
 // https://astro.build/config
 export default defineConfig({
@@ -18,4 +19,14 @@ export default defineConfig({
     allowedDomains: [{ hostname: 'localhost' }],
   },
   adapter: cloudflare(),
+  vite: {
+    plugins: [
+      // On v10, auto-instrumentation is opt-in.
+      sentryCloudflareVitePlugin({
+        _experimental: {
+          autoInstrumentation: true,
+        },
+      }),
+    ],
+  },
 });
diff --git a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/instrument.server.js b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/instrument.server.js
new file mode 100644
index 000000000000..eeb325d68c3f
--- /dev/null
+++ b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/instrument.server.js
@@ -0,0 +1,9 @@
+import { defineCloudflareOptions } from '@sentry/cloudflare';
+
+export default defineCloudflareOptions(env => ({
+  dsn: env.E2E_TEST_DSN,
+  environment: 'qa',
+  tracesSampleRate: 1.0,
+  tunnel: 'http://localhost:3031/', // proxy server
+  debug: true,
+}));
diff --git a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/sentry.server.config.js b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/sentry.server.config.js
deleted file mode 100644
index 8f1a839bc05f..000000000000
--- a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/sentry.server.config.js
+++ /dev/null
@@ -1,13 +0,0 @@
-import * as Sentry from '@sentry/cloudflare';
-import handler from '@astrojs/cloudflare/entrypoints/server';
-
-export default Sentry.withSentry(
-  env => ({
-    dsn: env.E2E_TEST_DSN,
-    environment: 'qa',
-    tracesSampleRate: 1.0,
-    tunnel: 'http://localhost:3031/', // proxy server
-    debug: true,
-  }),
-  handler,
-);
diff --git a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/worker-configuration.d.ts b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/worker-configuration.d.ts
index 03c757e9dcc2..96d062b4c7ac 100644
--- a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/worker-configuration.d.ts
+++ b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/worker-configuration.d.ts
@@ -5,7 +5,7 @@ interface __BaseEnv_Env {
 }
 declare namespace Cloudflare {
   interface GlobalProps {
-    mainModule: typeof import('./sentry.server.config');
+    mainModule: typeof import('@astrojs/cloudflare/entrypoints/server');
   }
   interface Env extends __BaseEnv_Env {}
 }
diff --git a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/wrangler.jsonc b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/wrangler.jsonc
index aeabb81d7c07..96df92ce1118 100644
--- a/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/wrangler.jsonc
+++ b/dev-packages/e2e-tests/test-applications/astro-6-cf-workers/wrangler.jsonc
@@ -2,7 +2,7 @@
   "compatibility_date": "2026-03-12",
   "compatibility_flags": ["global_fetch_strictly_public", "nodejs_als"],
   "name": "astro-6-cf-workers",
-  "main": "./sentry.server.config.js",
+  "main": "@astrojs/cloudflare/entrypoints/server",
   "assets": {
     "directory": "./dist",
     "binding": "ASSETS",
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/.gitignore b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/.gitignore
deleted file mode 100644
index 3f64191fe034..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/.gitignore
+++ /dev/null
@@ -1,4 +0,0 @@
-dist
-.wrangler
-test-results
-pnpm-lock.yaml
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/instrument.server.ts b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/instrument.server.ts
deleted file mode 100644
index 10d0f17fbcdb..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/instrument.server.ts
+++ /dev/null
@@ -1,10 +0,0 @@
-import { defineCloudflareOptions } from '@sentry/cloudflare';
-
-// The worker entry is a package, so the plugin reads this file from beside
-// the wrangler config.
-export default defineCloudflareOptions((env: { E2E_TEST_DSN: string }) => ({
-  dsn: env.E2E_TEST_DSN,
-  environment: 'qa',
-  tunnel: 'http://localhost:3031/',
-  tracesSampleRate: 1.0,
-}));
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/package.json b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/package.json
deleted file mode 100644
index 63c24d1f32f2..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/package.json
+++ /dev/null
@@ -1,29 +0,0 @@
-{
-  "name": "cloudflare-autoinstrument-package-entry",
-  "version": "0.0.0",
-  "private": true,
-  "type": "module",
-  "scripts": {
-    "build": "vite build",
-    "preview": "wrangler dev --var \"E2E_TEST_DSN:$E2E_TEST_DSN\" --log-level=$(test $CI && echo 'none' || echo 'log')",
-    "test": "playwright test",
-    "test:build": "pnpm install && pnpm build",
-    "test:assert": "pnpm test"
-  },
-  "dependencies": {
-    "@sentry/cloudflare": "file:../../packed/sentry-cloudflare-packed.tgz",
-    "worker-entry": "file:../../test-applications/cloudflare-autoinstrument-package-entry/worker-entry"
-  },
-  "devDependencies": {
-    "@cloudflare/vite-plugin": "^1.47.0",
-    "@cloudflare/workers-types": "^5.20260727.1",
-    "@playwright/test": "~1.56.0",
-    "@sentry-internal/test-utils": "link:../../../test-utils",
-    "vite": "^8.1.5",
-    "wrangler": "^4.114.0"
-  },
-  "volta": {
-    "node": "24.15.0",
-    "extends": "../../package.json"
-  }
-}
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/playwright.config.ts b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/playwright.config.ts
deleted file mode 100644
index 9633de63b272..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/playwright.config.ts
+++ /dev/null
@@ -1,12 +0,0 @@
-import { getPlaywrightConfig } from '@sentry-internal/test-utils';
-
-export default getPlaywrightConfig(
-  {
-    startCommand: 'pnpm preview',
-    port: 8787,
-  },
-  {
-    workers: '100%',
-    retries: 0,
-  },
-);
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/start-event-proxy.mjs b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/start-event-proxy.mjs
deleted file mode 100644
index 553dac81dc3c..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/start-event-proxy.mjs
+++ /dev/null
@@ -1,6 +0,0 @@
-import { startEventProxyServer } from '@sentry-internal/test-utils';
-
-startEventProxyServer({
-  port: 3031,
-  proxyServerName: 'cloudflare-autoinstrument-package-entry',
-});
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/tests/package-entry.test.ts b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/tests/package-entry.test.ts
deleted file mode 100644
index 770a32931013..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/tests/package-entry.test.ts
+++ /dev/null
@@ -1,32 +0,0 @@
-import { expect, test } from '@playwright/test';
-import { waitForError, waitForTransaction } from '@sentry-internal/test-utils';
-
-// The worker entry is a package with no Sentry calls. Any event that arrives
-// proves the plugin wrapped the module that wrangler's `main` resolved to.
-
-test('wraps a package entry with withSentry (options from instrument.server.ts)', async ({ baseURL }) => {
-  const transactionPromise = waitForTransaction('cloudflare-autoinstrument-package-entry', event => {
-    return event.contexts?.trace?.op === 'http.server';
-  });
-
-  const res = await fetch(baseURL!);
-  expect(res.status).toBe(200);
-
-  const transaction = await transactionPromise;
-  expect(transaction.contexts?.trace?.origin).toBe('auto.http.cloudflare');
-  // Only `instrument.server.ts` sets this environment.
-  expect(transaction.environment).toBe('qa');
-});
-
-test('captures an error thrown by a package entry', async ({ baseURL }) => {
-  const errorPromise = waitForError(
-    'cloudflare-autoinstrument-package-entry',
-    event => event.exception?.values?.[0]?.value === 'Thrown from a package entry',
-  );
-
-  const res = await fetch(`${baseURL}/throw`);
-  expect(res.status).toBe(500);
-
-  const error = await errorPromise;
-  expect(error.environment).toBe('qa');
-});
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/vite.config.ts b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/vite.config.ts
deleted file mode 100644
index 519dab4471c2..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/vite.config.ts
+++ /dev/null
@@ -1,15 +0,0 @@
-import { cloudflare } from '@cloudflare/vite-plugin';
-import { sentryCloudflareVitePlugin } from '@sentry/cloudflare/vite';
-import { defineConfig } from 'vite';
-
-export default defineConfig({
-  plugins: [
-    cloudflare(),
-    // On v10, auto-instrumentation is opt-in.
-    sentryCloudflareVitePlugin({
-      _experimental: {
-        autoInstrumentation: true,
-      },
-    }),
-  ],
-});
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/fetch-handler.js b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/fetch-handler.js
deleted file mode 100644
index 1d8a976634e6..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/fetch-handler.js
+++ /dev/null
@@ -1,11 +0,0 @@
-// Shaped like bundler output (e.g. `@astrojs/cloudflare`): the default export
-// is a specifier, not `export default <expr>`.
-var fetch_handler_default = {
-  async fetch(request) {
-    if (new URL(request.url).pathname === '/throw') {
-      throw new Error('Thrown from a package entry');
-    }
-    return new Response('ok');
-  },
-};
-export { fetch_handler_default as default };
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/package.json b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/package.json
deleted file mode 100644
index 08018b205e6e..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/worker-entry/package.json
+++ /dev/null
@@ -1,9 +0,0 @@
-{
-  "name": "worker-entry",
-  "version": "0.0.0",
-  "private": true,
-  "type": "module",
-  "exports": {
-    "./fetch-handler": "./fetch-handler.js"
-  }
-}
diff --git a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/wrangler.jsonc b/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/wrangler.jsonc
deleted file mode 100644
index 4f9bc84616ee..000000000000
--- a/dev-packages/e2e-tests/test-applications/cloudflare-autoinstrument-package-entry/wrangler.jsonc
+++ /dev/null
@@ -1,8 +0,0 @@
-{
-  "$schema": "node_modules/wrangler/config-schema.json",
-  "name": "cloudflare-autoinstrument-package-entry",
-  // A package export, not a file path. The Sentry plugin resolves it with Vite.
-  "main": "worker-entry/fetch-handler",
-  "compatibility_date": "2026-05-20",
-  "compatibility_flags": ["nodejs_compat"],
-}
diff --git a/packages/astro/src/integration/cloudflare.ts b/packages/astro/src/integration/cloudflare.ts
index c07f93ed16dc..d5447215dbf8 100644
--- a/packages/astro/src/integration/cloudflare.ts
+++ b/packages/astro/src/integration/cloudflare.ts
@@ -32,6 +32,10 @@ export function sentryCloudflareNodeWarningPlugin(): Plugin {
   };
 }
 
+// The Worker entry module: `@astrojs/cloudflare` v12 builds its own virtual entry, and v13+ builds
+// through `@cloudflare/vite-plugin`, whose entry ends in `export default mod.default ?? {};`.
+const WORKER_ENTRY_IDS = ['astrojs-ssr-virtual-entry', 'virtual:cloudflare/worker-entry'];
+
 /**
  * A Vite plugin that ensures the Sentry server config is loaded at the
  * top level of the Cloudflare Worker entry module, rather than only being
@@ -52,16 +56,14 @@ export function sentryCloudflareVitePlugin(): Plugin {
     enforce: 'post',
 
     transform(code, id) {
-      // Match the Astro SSR virtual entry — this becomes dist/_worker.js/index.js
-      // The resolved virtual module ID is `\0@astrojs-ssr-virtual-entry`
-      if (!id.includes('astrojs-ssr-virtual-entry')) {
+      if (!WORKER_ENTRY_IDS.some(entryId => id.includes(entryId))) {
         return undefined;
       }
 
       // In @astrojs/cloudflare v12, the virtual entry module structure is:
       // https://github.com/withastro/astro/blob/09bbdbb1e62c388eb405eeea03554c15e01f2957/packages/integrations/cloudflare/src/entrypoints/server.ts#L23
       // We need to wrap `default` with `withSentry` before it's exported.
-      const defaultExportMatch = code.match(/export\s+default\s+([\w.]+)\s*;/);
+      const defaultExportMatch = code.match(/export\s+default\s+([^;]+?)\s*;/);
 
       if (!defaultExportMatch) {
         return undefined;
diff --git a/packages/astro/src/integration/index.ts b/packages/astro/src/integration/index.ts
index 15b0f7c0c731..d509636443b5 100644
--- a/packages/astro/src/integration/index.ts
+++ b/packages/astro/src/integration/index.ts
@@ -166,6 +166,9 @@ export const sentryAstro = (options: SentryOptions = {}): AstroIntegration => {
 
         const isCloudflare = config?.adapter?.name?.startsWith('@astrojs/cloudflare');
         const isCloudflareWorkers = isCloudflare && !isCloudflarePages();
+        // With `_experimental.autoInstrumentation`, that plugin wraps the Worker entry, which inits
+        // the SDK from `instrument.server.*` or `env`, so our wrap and default init are not needed.
+        const usesCloudflareVitePlugin = isCloudflareWorkers && hasCloudflareVitePlugin(config);
 
         if (isCloudflare) {
           try {
@@ -189,7 +192,7 @@ export const sentryAstro = (options: SentryOptions = {}): AstroIntegration => {
             // This ensures Sentry.init() runs in dev mode (where the Vite plugin doesn't fire)
             // and also serves as the fallback for non-Cloudflare adapters in production.
             injectScript('page-ssr', buildSdkInitFileImportSnippet(pathToServerInit));
-          } else {
+          } else if (!usesCloudflareVitePlugin) {
             debug && logger.info('Using default server init.');
             injectScript('page-ssr', buildServerSnippet(options || {}));
           }
@@ -209,7 +212,9 @@ export const sentryAstro = (options: SentryOptions = {}): AstroIntegration => {
             debug && logger.info('Adding Cloudflare Vite plugin to wrap Worker entry with withSentry.');
             updateConfig({
               vite: {
-                plugins: [sentryCloudflareNodeWarningPlugin(), sentryCloudflareVitePlugin()],
+                plugins: usesCloudflareVitePlugin
+                  ? [sentryCloudflareNodeWarningPlugin()]
+                  : [sentryCloudflareNodeWarningPlugin(), sentryCloudflareVitePlugin()],
               },
             });
           } else if (isCloudflare) {
@@ -250,6 +255,32 @@ export const sentryAstro = (options: SentryOptions = {}): AstroIntegration => {
   };
 };
 
+// Of the sub-plugins `sentryCloudflareVitePlugin()` adds, only the one for
+// `_experimental.autoInstrumentation`, which wraps the Worker, has this prefix.
+const CLOUDFLARE_VITE_PLUGIN_NAME_PREFIX = 'sentry-cloudflare-';
+
+/**
+ * Whether the user added `sentryCloudflareVitePlugin()` from `@sentry/cloudflare/vite`. It is
+ * detected by name because importing it here would load `@sentry/cloudflare` and `wrangler` for
+ * every Astro app.
+ */
+function hasCloudflareVitePlugin(config: AstroConfig): boolean {
+  const pending: unknown[] = [config.vite?.plugins];
+  while (pending.length > 0) {
+    const plugin = pending.pop();
+    if (Array.isArray(plugin)) {
+      pending.push(...plugin);
+    } else if (
+      typeof plugin === 'object' &&
+      plugin !== null &&
+      String((plugin as { name?: unknown }).name).startsWith(CLOUDFLARE_VITE_PLUGIN_NAME_PREFIX)
+    ) {
+      return true;
+    }
+  }
+  return false;
+}
+
 const possibleFileExtensions = ['ts', 'js', 'tsx', 'jsx', 'mjs', 'cjs', 'mts'];
 
 function findDefaultSdkInitFile(type: 'server' | 'client'): string | undefined {
diff --git a/packages/astro/test/integration/cloudflareVitePlugin.test.ts b/packages/astro/test/integration/cloudflareVitePlugin.test.ts
new file mode 100644
index 000000000000..0464acd321e2
--- /dev/null
+++ b/packages/astro/test/integration/cloudflareVitePlugin.test.ts
@@ -0,0 +1,48 @@
+import { describe, expect, it } from 'vitest';
+import { sentryCloudflareVitePlugin } from '../../src/integration/cloudflare';
+
+function transform(code: string, id: string) {
+  const plugin = sentryCloudflareVitePlugin() as { transform: (code: string, id: string) => unknown };
+  return plugin.transform(code, id);
+}
+
+describe('sentryCloudflareVitePlugin', () => {
+  it('wraps the default export of the @astrojs/cloudflare v12 virtual entry', () => {
+    const code = ['const _exports = createExports(manifest);', 'export default _exports.default;'].join('\n');
+
+    expect(transform(code, '\0@astrojs-ssr-virtual-entry')).toEqual({
+      code: [
+        "import { withSentry } from '@sentry/cloudflare';",
+        'const _exports = createExports(manifest);',
+        'export default withSentry(() => undefined, _exports.default);',
+      ].join('\n'),
+      map: null,
+    });
+  });
+
+  it('wraps the default export of the @cloudflare/vite-plugin worker entry', () => {
+    const code = [
+      'import { getExportTypes } from "virtual:cloudflare/export-types";',
+      'import * as mod from "virtual:cloudflare/user-entry";',
+      'export * from "virtual:cloudflare/user-entry";',
+      'export default mod.default ?? {};',
+      'if (import.meta.hot) { import.meta.hot.accept(); }',
+    ].join('\n');
+
+    expect(transform(code, '\0virtual:cloudflare/worker-entry')).toEqual({
+      code: [
+        "import { withSentry } from '@sentry/cloudflare';",
+        'import { getExportTypes } from "virtual:cloudflare/export-types";',
+        'import * as mod from "virtual:cloudflare/user-entry";',
+        'export * from "virtual:cloudflare/user-entry";',
+        'export default withSentry(() => undefined, mod.default ?? {});',
+        'if (import.meta.hot) { import.meta.hot.accept(); }',
+      ].join('\n'),
+      map: null,
+    });
+  });
+
+  it('leaves other modules alone', () => {
+    expect(transform('export default handler;', '/src/pages/index.astro')).toBeUndefined();
+  });
+});
diff --git a/packages/astro/test/integration/index.test.ts b/packages/astro/test/integration/index.test.ts
index 3bc79d003a55..0d058e958ad0 100644
--- a/packages/astro/test/integration/index.test.ts
+++ b/packages/astro/test/integration/index.test.ts
@@ -353,6 +353,95 @@ describe('sentryAstro integration', () => {
     expect(sentryVitePluginSpy).toHaveBeenCalledTimes(0);
   });
 
+  // The plugin returns an array, so it arrives nested.
+  describe.each([
+    {
+      setup: 'sentryCloudflareVitePlugin({ _experimental: { autoInstrumentation: true } })',
+      plugins: [{ name: 'sentry-cloudflare-auto-instrument' }],
+    },
+    {
+      setup:
+        'sentryCloudflareVitePlugin({ _experimental: { autoInstrumentation: true, useDiagnosticsChannelInjection: true } })',
+      plugins: [{ name: 'code-transformer' }, { name: 'sentry-cloudflare-auto-instrument' }],
+    },
+  ])('with `$setup` from `@sentry/cloudflare/vite` in the vite config', ({ plugins }) => {
+    const cloudflareConfig = {
+      ...config,
+      adapter: { name: '@astrojs/cloudflare' },
+      vite: { plugins: [plugins] },
+    } as AstroConfig;
+
+    it('leaves the Worker wrap to that plugin', async () => {
+      const integration = sentryAstro({});
+
+      // @ts-expect-error - the hook exists and we only need to pass what we actually use
+      await integration.hooks['astro:config:setup']({
+        ...baseConfigHookObject,
+        updateConfig,
+        injectScript,
+        config: cloudflareConfig,
+      });
+
+      expect(updateConfig).toHaveBeenCalledWith({
+        vite: { plugins: [expect.objectContaining({ name: 'sentry-astro-cloudflare-suppress-node-warnings' })] },
+      });
+      expect(updateConfig).not.toHaveBeenCalledWith({
+        vite: { plugins: expect.arrayContaining([expect.objectContaining({ name: 'sentry-astro-cloudflare' })]) },
+      });
+    });
+
+    it('does not inject the default server init', async () => {
+      const integration = sentryAstro({});
+
+      // @ts-expect-error - the hook exists and we only need to pass what we actually use
+      await integration.hooks['astro:config:setup']({
+        ...baseConfigHookObject,
+        updateConfig,
+        injectScript,
+        config: cloudflareConfig,
+      });
+
+      expect(injectScript).not.toHaveBeenCalledWith('page-ssr', expect.anything());
+    });
+
+    it('still injects a server init file', async () => {
+      const integration = sentryAstro({ serverInitPath: 'my-server-init-path.js' });
+
+      // @ts-expect-error - the hook exists and we only need to pass what we actually use
+      await integration.hooks['astro:config:setup']({
+        ...baseConfigHookObject,
+        updateConfig,
+        injectScript,
+        config: cloudflareConfig,
+      });
+
+      expect(injectScript).toHaveBeenCalledWith('page-ssr', expect.stringContaining('my-server-init-path.js'));
+    });
+  });
+
+  // Without `_experimental.autoInstrumentation`, the plugin does not wrap the Worker on v10.
+  it('keeps its own Worker wrap when `@sentry/cloudflare/vite` only adds the orchestrion transform', async () => {
+    const integration = sentryAstro({});
+    const cloudflareConfig = {
+      ...config,
+      adapter: { name: '@astrojs/cloudflare' },
+      vite: { plugins: [[{ name: 'code-transformer' }]] },
+    } as AstroConfig;
+
+    // @ts-expect-error - the hook exists and we only need to pass what we actually use
+    await integration.hooks['astro:config:setup']({
+      ...baseConfigHookObject,
+      updateConfig,
+      injectScript,
+      config: cloudflareConfig,
+    });
+
+    expect(updateConfig).toHaveBeenCalledWith({
+      vite: { plugins: expect.arrayContaining([expect.objectContaining({ name: 'sentry-astro-cloudflare' })]) },
+    });
+    expect(injectScript).toHaveBeenCalledWith('page-ssr', expect.anything());
+  });
+
   it.each([{}, { enabled: true }])('injects client and server init scripts', async options => {
     const integration = sentryAstro(options);