From d7cac25b24e447796cf4b61156a160cc04a0cf6f Mon Sep 17 00:00:00 2001
From: Travis Bonnet <travisbonnet@gmail.com>
Date: Sat, 4 Apr 2026 21:34:19 -0500
Subject: [PATCH 1/2] fix(cloudflare): exclude queue consumers from prerender
 worker config

The prerender worker's config callback was spreading the entire
entryWorkerConfig, including queues.consumers. When Miniflare sees
two workers both registered as consumers of the same queue, it rejects
with ERR_MULTIPLE_CONSUMERS. The prerender worker only renders static
HTML and has no need for queue consumer registrations.

This fix destructures queues from the entry worker config and only
preserves queue producers (bindings) in the prerender worker config.

Closes #16199

Co-Authored-By: Tadao <tadao@travisfixes.com>
---
 .../fix-cf-prerender-queue-consumers.md       |  5 +++
 packages/integrations/cloudflare/src/index.ts |  8 +++--
 .../astro.config.mjs                          |  7 ++++
 .../prerender-queue-consumers/package.json    |  9 +++++
 .../src/pages/api.ts                          |  9 +++++
 .../src/pages/index.astro                     | 10 ++++++
 .../prerender-queue-consumers/wrangler.jsonc  | 18 ++++++++++
 .../test/prerender-queue-consumers.test.js    | 33 +++++++++++++++++++
 8 files changed, 97 insertions(+), 2 deletions(-)
 create mode 100644 .changeset/fix-cf-prerender-queue-consumers.md
 create mode 100644 packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/astro.config.mjs
 create mode 100644 packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/package.json
 create mode 100644 packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/api.ts
 create mode 100644 packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/index.astro
 create mode 100644 packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/wrangler.jsonc
 create mode 100644 packages/integrations/cloudflare/test/prerender-queue-consumers.test.js

diff --git a/.changeset/fix-cf-prerender-queue-consumers.md b/.changeset/fix-cf-prerender-queue-consumers.md
new file mode 100644
index 000000000000..99a09a150702
--- /dev/null
+++ b/.changeset/fix-cf-prerender-queue-consumers.md
@@ -0,0 +1,5 @@
+---
+'@astrojs/cloudflare': patch
+---
+
+Fixes `ERR_MULTIPLE_CONSUMERS` error when using Cloudflare Queues with prerendered pages. The prerender worker config callback now excludes `queues.consumers` from the entry worker config, since the prerender worker only renders static HTML and should not register as a queue consumer. Queue producers (bindings) are preserved.
diff --git a/packages/integrations/cloudflare/src/index.ts b/packages/integrations/cloudflare/src/index.ts
index 5e7c4481f619..5230da05d624 100644
--- a/packages/integrations/cloudflare/src/index.ts
+++ b/packages/integrations/cloudflare/src/index.ts
@@ -181,11 +181,15 @@ export default function createIntegration({
 						experimental: {
 							prerenderWorker: {
 								config(_, { entryWorkerConfig }) {
+									const { queues, ...restWorkerConfig } = entryWorkerConfig;
 									return {
-										...entryWorkerConfig,
+										...restWorkerConfig,
 										name: 'prerender',
+										...(queues?.producers?.length && {
+											queues: { producers: queues.producers },
+										}),
 										...(needsImagesBinding &&
-											!entryWorkerConfig.images && {
+											!restWorkerConfig.images && {
 												images: { binding: imagesBindingName },
 											}),
 									};
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/astro.config.mjs b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/astro.config.mjs
new file mode 100644
index 000000000000..339f0e2a49c0
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/astro.config.mjs
@@ -0,0 +1,7 @@
+import cloudflare from '@astrojs/cloudflare';
+import { defineConfig } from 'astro/config';
+
+export default defineConfig({
+	adapter: cloudflare(),
+	output: 'server',
+});
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/package.json b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/package.json
new file mode 100644
index 000000000000..5e57f22f1754
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/package.json
@@ -0,0 +1,9 @@
+{
+  "name": "@test/astro-cloudflare-prerender-queue-consumers",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "@astrojs/cloudflare": "workspace:*",
+    "astro": "workspace:*"
+  }
+}
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/api.ts b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/api.ts
new file mode 100644
index 000000000000..3060e9427491
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/api.ts
@@ -0,0 +1,9 @@
+import type { APIRoute } from 'astro';
+
+export const prerender = false;
+
+export const GET: APIRoute = async () => {
+	return new Response(JSON.stringify({ ok: true }), {
+		headers: { 'Content-Type': 'application/json' },
+	});
+};
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/index.astro b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/index.astro
new file mode 100644
index 000000000000..55e12f5dd94a
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/src/pages/index.astro
@@ -0,0 +1,10 @@
+---
+// This page is prerendered by default (output: 'server' with no opt-out)
+// Actually, in output: 'server' mode, pages are server-rendered by default.
+// We explicitly mark this as prerendered.
+export const prerender = true;
+---
+<html>
+<head><title>Prerendered</title></head>
+<body><h1>Prerendered Page</h1></body>
+</html>
diff --git a/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/wrangler.jsonc b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/wrangler.jsonc
new file mode 100644
index 000000000000..6ec9e7179b12
--- /dev/null
+++ b/packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers/wrangler.jsonc
@@ -0,0 +1,18 @@
+{
+  "name": "prerender-queue-consumers",
+  "main": "@astrojs/cloudflare/entrypoints/server",
+  "compatibility_date": "2026-01-28",
+  "queues": {
+    "consumers": [
+      {
+        "queue": "my-queue"
+      }
+    ],
+    "producers": [
+      {
+        "binding": "MY_QUEUE",
+        "queue": "my-queue"
+      }
+    ]
+  }
+}
diff --git a/packages/integrations/cloudflare/test/prerender-queue-consumers.test.js b/packages/integrations/cloudflare/test/prerender-queue-consumers.test.js
new file mode 100644
index 000000000000..c44729c698e9
--- /dev/null
+++ b/packages/integrations/cloudflare/test/prerender-queue-consumers.test.js
@@ -0,0 +1,33 @@
+import * as assert from 'node:assert/strict';
+import { after, before, describe, it } from 'node:test';
+import { loadFixture } from './_test-utils.js';
+
+describe('Prerender with queue consumers', () => {
+	let fixture;
+	let previewServer;
+
+	before(async () => {
+		fixture = await loadFixture({
+			root: './fixtures/prerender-queue-consumers/',
+		});
+		await fixture.build();
+		previewServer = await fixture.preview();
+	});
+
+	after(async () => {
+		previewServer.stop();
+	});
+
+	it('builds and previews without ERR_MULTIPLE_CONSUMERS', async () => {
+		// The prerendered page should be accessible
+		const res = await fixture.fetch('/');
+		const html = await res.text();
+		assert.ok(html.includes('Prerendered Page'));
+	});
+
+	it('serves the SSR endpoint', async () => {
+		const res = await fixture.fetch('/api');
+		const json = await res.json();
+		assert.deepEqual(json, { ok: true });
+	});
+});

From cb44e40a467ad44ec89683774465ab059401d6ac Mon Sep 17 00:00:00 2001
From: Travis Bonnet <travisbonnet@gmail.com>
Date: Tue, 7 Apr 2026 00:38:51 -0500
Subject: [PATCH 2/2] chore: update pnpm lockfile

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
---
 pnpm-lock.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 51689c6b75e8..a8f1694837cc 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -4976,6 +4976,15 @@ importers:
         specifier: workspace:*
         version: link:../../../../../astro
 
+  packages/integrations/cloudflare/test/fixtures/prerender-queue-consumers:
+    dependencies:
+      '@astrojs/cloudflare':
+        specifier: workspace:*
+        version: link:../../..
+      astro:
+        specifier: workspace:*
+        version: link:../../../../../astro
+
   packages/integrations/cloudflare/test/fixtures/prerender-styles:
     dependencies:
       '@astrojs/cloudflare':