Guide
v0: environment variables missing on the published app
Updated
Your v0 app works in the preview. On the published site a feature fails or a page breaks because a value it reads is empty.
Why it happens
v0 deploys to Vercel. Working branches get preview deployments, while publishing updates the production deployment. A variable only reaches a deployment if it is set for that environment and the deployment was made after it was saved.
Possible causes
- The variable is set for Preview only, so it is missing in Production.
- The variable was added after the live deployment was made, and changes only apply to new deployments.
- A value used in browser code does not have the NEXT_PUBLIC_ prefix, so browser code cannot read it.
- A database or integration value was never provisioned for the project.
- The latest build failed, so the live site is still running the older deployment.
You can't see it yourself
You're signed in, your customers aren't. The preview has everything you set while building. The published site is a different environment, and only visitors to it see the gap.
Related: It works in the preview but breaks after I deploy · A button on my app does nothing after I published it · My app is stuck on a loading spinner after I publish it
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