Take a v0 App to Production

To take a v0 app to production, treat it as what it is: a Next.js application on Vercel whose interface is usually ahead of its security. Check every Server Action and route handler for authentication and ownership checks, keep secrets out of NEXT_PUBLIC_ variables, give the connected database its own access rules, move to a commercial Vercel plan, and route changes through GitHub with tests. Easify's €99 Prototype Check returns the top security and data risks in writing within 48 hours.

v0 is the most conventional of the AI app builders. Its docs describe working with Next.js, Tailwind and shadcn/ui, and every project deploys to Vercel. That is good news: the code is a framework developers already know, and the path to production is well documented. It also means the risks are Next.js risks, which are subtler than "the database is open".

At a glance

How a v0 app is put together

Unlike Lovable or Bolt, v0 does not bring a backend of its own. Its database docs list integrations with Neon, Supabase, Upstash and Vercel Blob. Adding one provisions an account with that provider and adds the connection variables to your project. Authentication is whatever v0 wired in at your request: Supabase Auth, an auth library, or a hosted provider.

With GitHub connected, v0 pushes to a working branch, each branch gets a preview deployment, and publishing merges a pull request into the base branch. GitHub becomes the source of truth for the code. That is the best starting point for CI of any tool in this series, if you use it.

The risks specific to v0 apps

Server Actions are public endpoints

Next.js handles form submissions and mutations with Server Actions. They look like functions inside a component, which makes them easy to forget are endpoints. The Next.js data security guide is explicit: you "should still treat Server Actions as reachable via direct POST requests and verify authentication and authorization inside each one", and a page-level auth check "does not extend to the Server Actions defined within it".

The pattern to look for in generated code is an action such as deleteProject(id) that checks the user is logged in, or checks nothing, and never checks that the project belongs to them. That is an insecure direct object reference: any logged-in user can delete anyone's project by sending a different ID. The same applies to route.ts handlers.

Auth only in middleware

Redirecting logged-out users in middleware (called proxy in recent Next.js versions) is fine as a convenience. It is not a security boundary on its own. CVE-2025-29927 let attackers skip Next.js middleware entirely with a crafted header in unpatched versions, and every route that relied solely on middleware for authorisation was exposed. Keep Next.js patched, and check permissions again where the data is read or changed.

Secrets and the NEXT_PUBLIC_ prefix

Next.js inlines any variable prefixed NEXT_PUBLIC_ into the JavaScript sent to the browser at build time. A database URL, a Stripe secret key or an AI provider key with that prefix is published to every visitor. Generated code sometimes adds the prefix to make an error go away. Search for it and read each one.

A related leak: passing a whole database record from a Server Component to a Client Component sends every field to the browser, including ones the screen never shows. Next.js recommends a server-only data access layer that returns only the fields the interface needs.

The database behind the integration

If the integration is Supabase and any code talks to it from the browser, row-level security applies exactly as it does in a Lovable app: every table needs policies that restrict rows to their owner. If the database is Neon or another Postgres reached only from the server, there is no RLS safety net by default, so every query must filter by the current user in code.

v0's own docs note that it can generate and execute SQL against SQL integrations, "including creating, updating, and dropping tables". Point v0 at a development database or a branch, never at the one holding customer data.

Payments

Stripe belongs in a route handler that verifies the webhook signature and handles duplicate events, with entitlements granted only from the webhook. Route handlers on Vercel run as functions, so the webhook needs the raw request body for verification; code that parses JSON first will fail signature checks, and the tempting "fix" is to delete the check. Make sure nobody did.

Scaling on serverless

Under load, Vercel runs many function instances at once, and each one can open its own database connection. Use the pooled connection string your provider offers, or you will run out of connections at the first real spike. Watch function duration limits for slow work such as PDF generation or AI calls, and move long jobs to a queue. Check Vercel's usage pricing against your expected traffic, especially image optimisation and function time.

Tests, previews and environments

Vercel sets environment variables separately for Production, Preview and Development. A common mistake is a preview deployment pointed at the production database, so every branch v0 creates can write to live data. Give previews their own database. Then add CI on the GitHub repository: type check, lint, and end-to-end tests on sign-up, the core action and payment, with branch protection so v0's pull requests cannot merge until they pass. v0's docs confirm it respects GitHub branch protection and required reviews.

Hosting, plans and lock-in

Vercel's fair use guidelines restrict Hobby to non-commercial personal use, and count taking payments or advertising a product as commercial. A startup on Hobby is on the wrong plan.

Lock-in is the lowest of the four tools in this series. Next.js is open source and can be self-hosted on Node.js or Docker; this site, built on Next.js, runs in Docker on our own server. What does not move for free: Vercel Blob and other platform storage, Vercel-specific configuration such as cron jobs in vercel.json, and any reliance on Vercel's image optimisation and edge network. Staying on Vercel is often the right call; it is good to know you could leave.

A self-check you can run today

1. Search for NEXT_PUBLIC_ and confirm none of the values is a secret.
2. Open every file containing 'use server' and every route.ts. Does each one check the user, and that the record belongs to them?
3. Find where the app decides who is an admin. Is it checked on the server for every admin action?
4. Check your Next.js version against the fixed releases listed for CVE-2025-29927.
5. In Vercel, compare the Production and Preview environment variables. Do previews use a separate database?
6. If you use Supabase from the browser, confirm RLS on every table.
7. Confirm the Vercel plan is Pro or above if the product is commercial.
8. Check the Stripe webhook handler verifies signatures with the raw body.
9. Confirm main is protected and something runs tests before a merge.

When to stay on v0, and when to move off

Stay on v0 for interface work. It is very good at it, and with GitHub sync and branch protection you can keep using it for screens and components while developers own the server code.

Split the work once you have users: v0 for UI changes, reviewed pull requests for anything in 'use server' files, route handlers, auth, database access or payments.

Move off it when v0's pull requests start fighting a hand-written data layer, or when most changes are backend work it is not suited to. Moving off v0 does not mean moving off Next.js or Vercel; the app stays the same, only the way changes are made is different.

When not to hire us: if the app is a marketing site or a clickable prototype with no accounts or payments, you probably need a Vercel Pro plan and a domain, not a review.

What the €99 Prototype Check covers

The Prototype Check is a person reviewing the repository and the live app, for products built with v0, Lovable, Bolt, Replit, Cursor or similar. For a v0 app it focuses on:

• Server Actions and route handlers: authentication, ownership checks and input validation;
• where auth is enforced, and whether middleware is the only line;
• NEXT_PUBLIC_ variables, and data passed to Client Components;
• the database integration and its access rules;
• the Stripe webhook and how entitlements are granted;
• environments, previews and the Vercel plan.

Within 48 hours you receive the top security and data risks in writing, then a 15-minute call. Request it with the Prototype Check form; we reply within one business day with a payment link.

What happens after it

You can fix the findings yourself or hand them to any Next.js developer. If you want Easify to carry on, the next step is the five-day audit, quoted after the Prototype Check, then the work it identifies. We have built production Next.js before, including the Dealtous marketplace, with seller verification, authentication and an integrated payment system. Where a rebuild is cheaper than repair, it is scoped like any MVP: typically €5,000 to €25,000 over 4 to 12 weeks, at €25 to €45 an hour with a €1,000 minimum project. The €99 is credited against the build if you hire us.

We are in Budapest, working remotely across Europe on CET, in English or Hungarian, with our engineering team in India. For other tools, see the guides for Lovable and Bolt.