v0 Component Launch Security Checklist: 14 Items Before Going Live

TL;DR

v0 generates React/Next.js components that need integration work before production. Replace all placeholder data, add server-side validation, verify authentication is implemented correctly, and ensure any API calls use secure endpoints. The UI is ready, but the security layer is your job.

v0 by Vercel generates beautiful React components and page layouts. Since it focuses on UI, the generated code often uses placeholder data and mock functions. Before launching, you need to replace these with secure, production-ready implementations.

Replace Placeholder Code 4

::checklist-item{label="Remove all mock/placeholder data" description="Search for "placeholder", "mock", "dummy", "example" and replace with real data sources"} ::

Replace console.log statementsv0 may include debug logs. Remove or replace with proper logging.

Implement real form handlersForms may have stub onSubmit handlers. Add real validation and submission.

::checklist-item{label="Connect to real API endpoints" description="Replace any fetch("/api/example") calls with actual backend endpoints"} ::

Input and Data Security 4

Add server-side input validationClient validation can be bypassed. All inputs must validate on the server.

Check for dangerouslySetInnerHTMLIf used, ensure content is sanitized. This bypasses React's XSS protection.

Verify file upload handling (if applicable)Validate types, limit sizes, and scan uploads if the component handles files

Test with malicious inputEnter <script> tags and SQL injection strings in all form fields

Authentication (If Required) 3

Add authentication to protected componentsv0 doesn't add auth by default. Implement using NextAuth, Clerk, or similar.

Protect API routesAny API routes you add need authentication middleware

Test unauthorized accessTry accessing protected routes directly without logging in

Deployment Security 3

Search for hardcoded API keysCheck for any sk_, pk_, api_key, or password strings in the code

Set environment variables in VercelAny API keys should be in Vercel environment settings, not code

Verify HTTPS is workingVercel handles this, but confirm http:// redirects to https://

Understanding v0's Output

v0 is a UI generation tool, not a full-stack application builder. It creates components with React and Tailwind CSS that look great and have basic interactivity, but they're designed to be integrated into a larger application.

This means security features like authentication, authorization, and input validation are typically not included. The generated code is a starting point for the visual layer, with the expectation that you'll add the backend and security layer yourself.

v0 generates React components that are generally safe from XSS because React escapes output by default. However, v0 code often uses placeholder data and mock functions that need to be replaced with secure implementations before production use.

What should I check before using v0 components in production?

Replace all placeholder data with real implementations, add proper authentication if needed, validate any user inputs on the server side, ensure API calls use secure endpoints, and verify no hardcoded credentials exist in the generated code.

Does v0 add authentication automatically?

No, v0 focuses on UI components and doesn't include authentication. You'll need to add authentication using a service like NextAuth.js, Clerk, or Auth0 if your application requires protected routes.