Vibe Coding Works—Until Someone Else Logs In
Why does my AI-built app break when a second user logs in? A worked guide to the hidden tradeoffs, practical checks, and implementation decisions.
Why does my AI-built app break when a second user logs in? A worked guide to the hidden tradeoffs, practical checks, and implementation decisions.
How do I test user isolation before launch?
Create two ordinary test accounts and one explicitly shared resource in a development environment. Give each account a distinct private record with an unmistakable marker. Verify that each account can retrieve its own record, cannot retrieve the other's record by identifier, and can access the shared record only in the permitted way.
Exercise the server endpoints directly as well as the interface. Hiding an edit button does not establish that the edit request is rejected. Test read, update, delete, export, and file-download operations with the wrong account, then confirm that failures do not reveal private record contents in the response or logs.
Repeat the important checks after switching accounts in the same browser and after warming any relevant cache. Add a background-job case if the app sends email, generates documents, or processes uploads. A job should retain the correct ownership context rather than accidentally using whichever user or organization a worker last handled.
Keep a small regression suite around these boundaries because they protect actual user data. A useful result records the endpoint, requesting account, target owner, expected outcome, and observed outcome. Launch only after the access rules match the product's intended sharing model, including explicit collaboration cases rather than an oversimplified rule that nothing can ever be shared.
Comments 0
Share how you would use this prompt or suggest a useful improvement.