Imported from jeremylongshore/tons-of-skills-marketplace (
skills/.curated/vercel-hello-world/SKILL.md). Install upstream withnpx skills add jeremylongshore/tons-of-skills-marketplace --skill vercel-hello-world. Copyright stays with the author (MIT).
Vercel Hello World
Overview
Deploy a minimal project to Vercel with a static page and a serverless API route. Confirms your CLI auth, project structure, and deployment pipeline work end to end.
Prerequisites
- Completed
vercel-install-authsetup - Vercel CLI installed and authenticated
- Node.js 18+
Instructions
Step 1: Create Project Structure
mkdir my-vercel-app && cd my-vercel-app
npm init -yCreate the static landing page:
<!-- public/index.html -->
<!DOCTYPE html>
<html>
<head><title>Hello Vercel</title></head>
<body>
<h1>Hello from Vercel</h1>
<p id="result">Loading...</p>
<script>
fetch('/api/hello')
.then(r => r.json())
.then(d => document.getElementById('result').textContent = d.message);
</script>
</body>
</html>Step 2: Create Serverless API Route
// api/hello.ts
import type { VercelRequest, VercelResponse } from '@vercel/node';
export default function handler(req: VercelRequest, res: VercelResponse) {
res.status(200).json({
message: 'Hello from Vercel Serverless Function!',
timestamp: new Date().toISOString(),
region: process.env.VERCEL_REGION || 'local',
});
}Install the types:
npm install --save-dev @vercel/node typescriptStep 3: Add vercel.json Configuration
{
"rewrites": [
{ "source": "/api/(.*)", "destination": "/api/$1" }
],
"headers": [
{
"source": "/api/(.*)",
"headers": [
{ "key": "Cache-Control", "value": "s-maxage=0, stale-while-revalidate" }
]
}
]
}Step 4: Deploy Preview
# Deploy to a preview URL (not production)
vercel
# Output:
# Vercel CLI 39.x.x
# 🔗 Linked to your-team/my-vercel-app
# 🔍 Inspect: https://vercel.com/your-team/my-vercel-app/xxx
# ✅ Preview: https://my-vercel-app-xxx.vercel.appStep 5: Test the Deployment
# Test static page
curl -s https://my-vercel-app-xxx.vercel.app/ | head -5
# Test API route
curl -s https://my-vercel-app-xxx.vercel.app/api/hello | jq .
# {
# "message": "Hello from Vercel Serverless Function!",
# "timestamp": "2026-03-22T12:00:00.000Z",
# "region": "iad1"
# }Step 6: Promote to Production
# Deploy directly to production
vercel --prod
# Or promote the preview deployment
vercel promote https://my-vercel-app-xxx.vercel.appVercel System Environment Variables
These are available in every function at runtime:
| Variable | Value |
|---|---|
VERCEL |
"1" — always set on Vercel |
VERCEL_ENV |
"production", "preview", or "development" |
VERCEL_URL |
Deployment URL (no protocol) |
VERCEL_REGION |
Function region (e.g., iad1) |
VERCEL_GIT_COMMIT_SHA |
Git commit hash |
VERCEL_GIT_COMMIT_MESSAGE |
Git commit message |
Output
- Static page served from Vercel CDN
- Serverless API route returning JSON at
/api/hello - Preview URL for testing before production
- Production deployment live on your domain
Error Handling
| Error | Cause | Solution |
|---|---|---|
404 NOT_FOUND on /api/hello |
File not in api/ directory |
Move file to project root api/ folder |
FUNCTION_INVOCATION_FAILED |
Runtime error in handler | Check function logs: vercel logs <url> |
BUILD_FAILED |
TypeScript compilation error | Run npx tsc --noEmit locally first |
NO_RESPONSE_FROM_FUNCTION |
Handler didn't call res.send/json |
Ensure all code paths return a response |
FUNCTION_PAYLOAD_TOO_LARGE |
Response body > 4.5 MB | Paginate or stream the response |
Examples
Deploy a harmless preview before connecting a domain
Create a minimal route that returns a static health response and deploy it with vercel --yes from a feature branch. Test the generated preview URL, verify the commit SHA in the deployment metadata, and keep environment variables absent unless the example requires them. Only after the preview is healthy should a reviewer approve the production workflow; do not point a customer domain at an unreviewed hello-world deployment.
Resources
Next Steps
Proceed to vercel-local-dev-loop for development workflow setup.