Vercel deployments

Vercel Deployments

Ship web apps quickly with preview environments and managed edge infrastructure.

When to Use This Skill

Use this skill when:

• Deploying Next.js, SvelteKit, Nuxt, or static sites
• Setting up preview environments for every PR
• Configuring edge functions and serverless APIs
• Managing environment variables across preview/production
• Setting up custom domains and redirects

Prerequisites

• Node.js 18+
• Vercel account (free tier works for personal projects)
• Git repository (GitHub, GitLab, or Bitbucket)

Quick Start

# Install CLI
npm i -g vercel

# Login and link project
vercel login
vercel link

# Deploy to preview
vercel

# Deploy to production
vercel --prod

# Pull environment variables locally
vercel env pull .env.local

Project Configuration

// vercel.json
{
  "framework": "nextjs",
  "buildCommand": "npm run build",
  "outputDirectory": ".next",
  "installCommand": "npm ci",
  "regions": ["iad1", "sfo1", "cdg1"],
  "headers": [
    {
      "source": "/api/(.*)",
      "headers": [
        { "key": "Cache-Control", "value": "no-store" },
        { "key": "X-Content-Type-Options", "value": "nosniff" }
      ]
    },
    {
      "source": "/(.*)",
      "headers": [
        { "key": "X-Frame-Options", "value": "DENY" },
        { "key": "Strict-Transport-Security", "value": "max-age=63072000; includeSubDomains" }
      ]
    }
  ],
  "redirects": [
    { "source": "/blog/:slug", "destination": "/posts/:slug", "permanent": true }
  ],
  "rewrites": [
    { "source": "/api/v1/:path*", "destination": "https://api.example.com/:path*" }
  ]
}

Environment Variables

# Add environment variables
vercel env add DATABASE_URL production
vercel env add DATABASE_URL preview
vercel env add NEXT_PUBLIC_API_URL production

# List all env vars
vercel env ls

# Pull to local .env.local
vercel env pull .env.local

# Remove an env var
vercel env rm SECRET_KEY production

Environment Separation Pattern

# Production — real credentials
vercel env add DATABASE_URL production <<< "postgresql://prod-host:5432/app"
vercel env add STRIPE_SECRET_KEY production

# Preview — staging/test credentials
vercel env add DATABASE_URL preview <<< "postgresql://staging-host:5432/app"
vercel env add STRIPE_SECRET_KEY preview   # Use test mode key

# Development — local values
vercel env add DATABASE_URL development <<< "postgresql://localhost:5432/app"

Edge Functions

// app/api/geo/route.ts — Edge API route (Next.js App Router)
import { NextRequest } from 'next/server';

export const runtime = 'edge';

export function GET(request: NextRequest) {
  const country = request.geo?.country || 'US';
  const city = request.geo?.city || 'Unknown';

  return Response.json({
    country,
    city,
    region: request.geo?.region,
    timestamp: new Date().toISOString(),
  });
}

// middleware.ts — Edge middleware for auth/redirects
import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

export function middleware(request: NextRequest) {
  // Block non-US traffic from admin
  if (request.nextUrl.pathname.startsWith('/admin')) {
    if (request.geo?.country !== 'US') {
      return NextResponse.redirect(new URL('/blocked', request.url));
    }
  }

  // Add security headers
  const response = NextResponse.next();
  response.headers.set('X-Request-Id', crypto.randomUUID());
  return response;
}

export const config = {
  matcher: ['/admin/:path*', '/api/:path*'],
};

GitHub Actions Integration

# .github/workflows/preview.yml
name: Vercel Preview
on: pull_request

jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'

      - run: npm ci
      - run: npm run lint
      - run: npm run test

      - name: Deploy to Vercel Preview
        id: deploy
        run: |
          npm i -g vercel
          URL=$(vercel --token ${{ secrets.VERCEL_TOKEN }} --yes)
          echo "url=$URL" >> "$GITHUB_OUTPUT"

      - name: Comment PR with preview URL
        uses: actions/github-script@v7
        with:
          script: |
            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: `Preview deployed: ${{ steps.deploy.outputs.url }}`
            });

CLI Commands Reference

# Deployments
vercel                          # Deploy to preview
vercel --prod                   # Deploy to production
vercel rollback                 # Rollback last production deploy
vercel promote <url>            # Promote preview to production

# Domains
vercel domains add example.com
vercel domains ls
vercel certs ls

# Logs
vercel logs <deployment-url>
vercel logs <deployment-url> --follow

# Project management
vercel project ls
vercel project rm <name>

# Inspect deployment
vercel inspect <deployment-url>

Production Guardrails

• Require preview checks before merge (GitHub branch protection)
• Separate preview and production environment variables — never share API keys
• Use branch protection with required deployment status checks
• Monitor function duration and cold start behavior in Vercel Analytics
• Set spend limits in Vercel dashboard to prevent cost surprises
• Enable Vercel Firewall for DDoS and bot protection
• Use vercel.json headers for security (CSP, HSTS, X-Frame-Options)

Monitoring & Analytics

# Enable Speed Insights in Next.js
npm install @vercel/speed-insights

# Enable Web Analytics
npm install @vercel/analytics

// app/layout.tsx
import { Analytics } from '@vercel/analytics/react';
import { SpeedInsights } from '@vercel/speed-insights/next';

export default function RootLayout({ children }) {
  return (
    <html>
      <body>
        {children}
        <Analytics />
        <SpeedInsights />
      </body>
    </html>
  );
}

Troubleshooting

Issue	Solution
Build fails	Check vercel logs, verify Node.js version in engines field
Env vars missing	Run vercel env pull, check variable scope (preview vs production)
Edge function timeout	Edge has 30s limit; move heavy work to serverless (no runtime = 'edge')
Cold starts slow	Use edge runtime where possible, reduce bundle size
Domain not working	Check DNS propagation, verify vercel domains configuration

Related Skills

• github-actions — Automated deployment gates
• cloudflare-pages — Alternative edge hosting
• ssl-tls-management — Custom certificate setup