Secure Cursor Deployment: A Practical Launch Check

A secure Cursor deployment needs checks against the app people will actually use. Reviewing a generated diff is useful, but a production build can still expose a secret, use the wrong environment, or trust a browser-supplied account ID.

This guide is for builders shipping a web app from Cursor. Start with the Cursor security review guide for code changes, then use this checklist on your own deployment before sharing the URL.

1. Write down what you are shipping

Record the commit, production hostname, hosting project, database project, and build time. Check whether the link is a preview or the production release. A clean preview does not establish that production uses the same configuration.

Make a small inventory of the app's boundaries: public pages, signed-in pages, server routes, database access, uploads, and payment callbacks. Beside each one, write who is allowed to use it and what data it returns.

2. Inspect the public build for the wrong kind of key

Open your deployed page in a clean browser session and inspect the JavaScript files loaded in the Network panel. Look for credentials you know belong exclusively on your server. Also check source maps if you intentionally publish them.

In Next.js, statically referenced variables with a NEXT_PUBLIC_ prefix are inlined into browser JavaScript at build time. Changing a public environment variable in the hosting dashboard therefore requires a new build to update that value. See the Next.js environment variable documentation.

• Keep server credentials out of client components and public environment variables.

• Check the repository's ignore rules before committing local environment files.

• If a real secret was published, revoke or rotate it at its provider, then rebuild and inspect the replacement deployment. Removing it from a file does not invalidate the exposed credential.

A Supabase publishable key or legacy anon key is designed for public clients; it is not automatically a secret leak. A secret key or legacy service-role key belongs on trusted server infrastructure. Check the Supabase key types before treating every key-shaped string as the same issue.

3. Test authorization with disposable data

Use a staging environment you own, two disposable accounts, and a harmless record such as “deployment-check-A.” Avoid customer data. First confirm that account A can perform its intended actions on its own record.

1. Sign out and try opening the same private route. The response must not include the private record.

2. Sign in as account B and try reading A's record through the normal UI and the corresponding request.

3. In staging, check that B cannot change or delete A's disposable record through the application's intended API.

4. Verify that the server derives identity from the validated session and checks ownership. A hidden button or a browser-supplied user ID is insufficient evidence.

The desired result depends on the app: a public profile may be intentionally readable, while a private invoice should not be. Define that distinction before interpreting a response. For a Supabase backend, use the two-user RLS testing guide alongside this check.

4. Verify the production configuration

After staging passes, check the production hostname, HTTPS, authentication redirect destinations, and the selected database project. Confirm that debug pages and preview-only fixtures are absent. Exercise a normal sign-in and sign-out without creating unnecessary real transactions.

Keep a short release note with the deployed commit, checks completed, and unresolved findings. If the release needs a rollback, that record helps you identify the last deployment whose behavior you verified.

5. Run a public check, then review the remaining boundaries

The VibeShield instant scanner checks a limited public surface without signup, including security headers, TLS, cookies, and possible secrets in public HTML or JavaScript. It cannot prove that private routes, tenant isolation, or payment authorization are correct.

For a signed-in audit, create a free VibeShield account and choose the available tools. Active security tests require a paid entitlement and verified ownership of the exact hostname. Treat findings as evidence to investigate, apply the relevant change, and retest the deployed behavior.

Common questions

Does reviewing Cursor's terminal approvals secure the deployed app?

It helps control what the agent runs during development. It does not test your app's runtime authorization. Review Cursor's run-mode documentation and keep deployment checks separate in your release checklist.

When should I repeat these checks?

Repeat the relevant checks after changes to authentication, database policies, environment variables, dependencies, or deployment configuration. Keep the launch security checklist beside your release notes.