v0.dev Security Best Practices: From Prototype to Production
v0.dev by Vercel is amazing for rapidly prototyping UI components. But when it's time to go to production, there are critical security considerations you need to address.
v0 generates beautiful React components, but it's designed for UI prototyping—not production-ready security. This guide covers everything you need to know to deploy v0 components safely.
Understanding v0's Output
v0 generates client-side React components. This means:
- All code runs in the browser – Never put secrets in v0 components
- Components are UI-focused – You'll need to add your own API layer
- No built-in security – Input validation, auth checks, etc. are your responsibility
v0 is for UI, Not Security
v0 optimizes for visual design and React best practices, not security. Treat all v0 output as needing security review before production.
Securing API Integrations
When you ask v0 to create a component that fetches data or calls an API, it will often generate code that needs modification for production.
Problem: Client-Side API Calls
// v0 might generate this (not secure)
const response = await fetch('https://api.openai.com/v1/chat/completions', {
headers: {
'Authorization': `Bearer $${apiKey}`
}
});
Solution: Use API Routes
// Create an API route (app/api/chat/route.ts)
export async function POST(request: Request) {
const { message } = await request.json();
const response = await fetch('https://api.openai.com/...', {
headers: {
'Authorization': `Bearer $${process.env.OPENAI_API_KEY}`
}
});
return Response.json(await response.json());
}
// Your v0 component calls your API route instead
const response = await fetch('/api/chat', {
method: 'POST',
body: JSON.stringify({ message })
});
Input Validation & XSS Prevention
v0 components may use dangerouslySetInnerHTML or render user input without sanitization. Always review generated code for these patterns.
Red Flags to Watch For
dangerouslySetInnerHTMLwith user data- URL parameters rendered without validation
- Form submissions without CSRF protection
- Dynamic URLs constructed from user input
Safe Patterns
- Use React's built-in escaping (JSX automatically escapes content)
- Validate and sanitize all user inputs
- Use libraries like DOMPurify if you must render HTML
Vercel Security Configuration
When deploying to Vercel, add these security headers to protect your app:
// next.config.js
const securityHeaders = [
{ key: 'X-DNS-Prefetch-Control', value: 'on' },
{ key: 'Strict-Transport-Security', value: 'max-age=63072000; includeSubDomains; preload' },
{ key: 'X-Frame-Options', value: 'SAMEORIGIN' },
{ key: 'X-Content-Type-Options', value: 'nosniff' },
{ key: 'Referrer-Policy', value: 'origin-when-cross-origin' },
];
Additional Vercel Settings
- Enable Vercel Firewall for DDoS protection
- Use Vercel's encrypted environment variables for secrets
- Disable source maps in production
- Configure proper CORS for API routes
Server vs Client Components
Next.js 13+ uses React Server Components by default. Understanding the security implications is crucial:
Server Components
- + Can access secrets directly
- + Database queries are safe
- + Code never sent to browser
- - Can't use useState/effects
Client Components
- - Never put secrets here
- - All code visible to users
- - Needs API routes for data
- + Interactive features work
v0 Often Generates Client Components
Check for "use client" at the top of files. If present, never add API keys or sensitive logic to that file.
v0 to Production Checklist
Ready for Production?
Run a VAS security scan before you launch. We'll check your v0 components for vulnerabilities and give you fixes you can implement immediately.