Deploy Astro Site to Cloudflare Workers

Guide for setting up and deploying Astro sites to Cloudflare Workers with custom domains. This encodes tested patterns that avoid common pitfalls.

Critical Rule

Never run `wrangler deploy` or `wrangler pages deploy` locally. Deployments happen by pushing to git. The CI/CD pipeline (Cloudflare dashboard connected to GitHub) handles the rest. Local deploys create version drift and bypass any CI checks.

The only local wrangler commands you should run are diagnostic/read-only ones like wrangler whoami, wrangler deployments list, and wrangler dev (local preview).

Setup Checklist

Work through these steps in order. Each step has a verification check.

1. Install the Cloudflare Adapter

npm install @astrojs/cloudflare

Astro 6 also requires an explicit Vite 7 dependency to avoid build errors (require_dist is not a function):

npm install vite@^7

Verify: package.json has both @astrojs/cloudflare and vite: "^7" in dependencies.

2. Configure astro.config.mjs

The adapter should only activate for builds, not during local dev. Use this conditional pattern:

import { defineConfig } from 'astro/config';
import tailwindcss from '@tailwindcss/vite';
import cloudflare from '@astrojs/cloudflare';

export default defineConfig({
  site: 'https://your-domain.example.com',
  adapter: process.argv.includes('dev') ? undefined : cloudflare(),
  vite: {
    plugins: [tailwindcss()],
  },
});

The process.argv.includes('dev') check means astro dev runs without the adapter (faster, no worker emulation), while astro build uses it.

Verify: Run npm run dev and confirm no Cloudflare-related warnings in the console.

3. Create wrangler.toml

name = "your-project-name"
compatibility_date = "2025-03-28"
compatibility_flags = ["nodejs_compat"]

[assets]
directory = "./dist"

Pick a name that matches your Cloudflare Workers project name. This is the identifier Cloudflare uses, not the display name.

Verify: File exists at project root alongside package.json.

4. Create .gitignore

Ensure these entries are present:

node_modules/
dist/
.astro/
.wrangler/
.gstack/
.env
.env.*
.dev.vars*
!.dev.vars.example
!.env.example
.DS_Store

The .wrangler/ directory contains local build artifacts and deployment state that should never be committed.

5. Add Build Scripts

Ensure package.json has these scripts:

{
  "scripts": {
    "dev": "astro dev",
    "build": "astro build",
    "preview": "npm run build && wrangler dev"
  }
}

The preview script builds and then runs the Cloudflare worker locally so you can test the production behavior before pushing.

6. Verify the Build

npm run build

A successful build will show:

• [build] adapter: @astrojs/cloudflare
• Prerendered routes listed
• [build] Complete!

Common build failures:

• `require_dist is not a function`: Missing vite: "^7" in dependencies. Install it.
• `Cannot find module '@astrojs/cloudflare'`: Adapter not installed. Run npm install @astrojs/cloudflare.
• Hydration/SSR errors: Check that components using browser APIs are wrapped in client:only directives.

7. Push to Deploy

git add -A
git commit -m "chore: configure Cloudflare Workers deployment"
git push

The Cloudflare dashboard should be connected to the GitHub repo with:

• Build command: npm run build
• Build output directory: dist
• Branch: main

Custom Domains

Adding a Custom Domain

Add a routes entry to wrangler.toml:

routes = [
  { pattern = "subdomain.yourdomain.com", custom_domain = true }
]

Then commit and push. Cloudflare will automatically create the DNS record if the domain's zone is managed by Cloudflare.

Multiple Domains

routes = [
  { pattern = "www.yourdomain.com", custom_domain = true },
  { pattern = "yourdomain.com", custom_domain = true }
]

Verification and Debugging

After pushing a deployment, verify everything is working. Use the wrangler CLI and standard tools to diagnose issues without deploying locally.

Verify Deployment Status

Check that the latest deployment went through:

npx wrangler deployments list --name your-project-name

This shows all deployments with timestamps, authors, and version IDs. The most recent entry should match your latest push.

Verify the Workers Dev URL

Every worker gets a *.workers.dev URL automatically. Test it:

curl -sI https://your-project-name.<account>.workers.dev

You should get a 200 response. If this works but the custom domain doesn't, the issue is DNS, not the deployment.

DNS Debugging

If the custom domain doesn't resolve:

Step 1: Check DNS resolution

dig subdomain.yourdomain.com +short

If empty, there's no DNS record yet.

Step 2: Check if Cloudflare created the record

When using custom_domain = true in routes, Cloudflare should auto-create a DNS record in the zone. Check via the API:

# List DNS records for the zone
npx wrangler dns list yourdomain.com

Or check the Cloudflare dashboard: DNS > Records for the domain zone. Look for a CNAME or A record for the subdomain.

Step 3: Create the record manually if needed

If no record was auto-created, add a CNAME manually in the Cloudflare DNS dashboard:

• Type: CNAME
• Name: subdomain (just the subdomain part, not the full domain)
• Target: your-project-name.<account>.workers.dev
• Proxy status: Proxied (orange cloud)

Step 4: Wait and re-check

DNS propagation can take a few minutes even within Cloudflare. Re-check:

dig subdomain.yourdomain.com +short
curl -sI https://subdomain.yourdomain.com

Step 5: SSL issues

Cloudflare handles SSL automatically for proxied records. If you see certificate errors:

• Make sure the CNAME is proxied (orange cloud, not grey)
• Check that the domain zone has "Full" or "Full (strict)" SSL mode
• Wait a few minutes for the edge certificate to provision

Verify the Live Site

Once DNS resolves, do a full check:

# Check HTTP response and headers
curl -sI https://subdomain.yourdomain.com

# Verify correct content is served
curl -s https://subdomain.yourdomain.com | head -20

# Check a subpage works
curl -sI https://subdomain.yourdomain.com/some-page

Look for:

• HTTP/2 200 status
• cf-ray header (confirms Cloudflare is serving)
• server: cloudflare header
• Correct HTML content in the body

Common Issues

Tailing Logs

To see real-time errors from the deployed worker:

npx wrangler tail --name your-project-name

This streams logs from the production worker. Useful for debugging 500 errors, missing routes, or runtime exceptions.

Environment Variables

For secrets (API keys, tokens), use the Cloudflare dashboard or:

npx wrangler secret put MY_SECRET --name your-project-name

For non-secret config, add to wrangler.toml:

[vars]
PUBLIC_SITE_URL = "https://yourdomain.com"

Disabling the Workers Dev URL

After confirming the custom domain works, you can disable the .workers.dev URL:

workers_dev = false

Commit and push.