Connect with the Neon Vercel Integration

This guide describes how to connect using the Neon Vercel Integration from the Vercel marketplace. The integration connects your Vercel project to a Neon database and enables creating a database branch for each preview deployment.

About the Neon Vercel Integration

Vercel preview deployments enable teams to collaborate effectively by automatically creating an isolated, production-like environment for every commit. This allows changes to be previewed before they are merged into production.

However, when databases are involved, teams often use a single database containing dummy data for all preview deployments. This setup is not ideal for these reasons:

• If the shared database encounters an issue, so will all preview deployments.
• Changes to the shared database schema might break all previously created preview deployments, making it a productivity bottleneck.

Neon’s branching feature addresses these challenges. A branch is a copy-on-write clone of your data, so creating it only takes a few seconds. This makes it a scalable and cost-effective solution for preview deployments, enabling you to create a branch for each pull request.

When you push changes to the repository associated with your Vercel project, triggering a preview deployment, the integration automatically creates a branch in Neon and connects it to your preview deployment by setting Vercel preview environment variables.

Add the Neon Vercel Integration

This section describes how to add the Neon Vercel Integration to your Vercel project.

Prerequisites:

• A Vercel account.
• A Vercel project. If you do not have one, see Creating a project, in the Vercel documentation.
• The integration initially sets the DATABASE_URL environment variable for your Vercel Production and Development environments. When you create a preview deployment, the integration will also set this variable for your Preview environment. Make sure this variable does not already exist in your Vercel project settings. To use different Postgres variables with the Neon integration, see Manage Vercel environment variables.

To add the integration:

1. Navigate to the Neon Vercel Integration page, and click Add integration.
2. Select a Vercel Account to add the integration to.
3. Select the Vercel projects to add the integration to. You can select All Projects or Specific Projects but be aware that you can only connect one Vercel project to one Neon project and vice versa. By selecting All projects, you are simply making the integration available to use with all of your Vercel projects.
4. Review the permissions required by the integration, and click Add Integration.
5. In the Integrate Neon dialog:

   1. Select a Vercel project.

   2. Select the Neon project that you want to connect to your Vercel project by selecting the Neon project, database, and role that Vercel will use to connect.

      The Create a branch for your development environment option creates a branch named vercel-dev and sets Vercel development environment variables for it. The vercel-dev branch is a clone of your project's primary branch (main) that you can modify without affecting data on your primary branch.

      note

      Branches created for preview deployments are created from the primary branch of your Neon project. Earlier versions of the integration created branches from the initial root branch of your Neon project, which is designated as the primary branch by default. Neon lets you change the primary branch. If you have an older version of the integration that creates branches from your project's root branch, and you want branches created from your primary branch instead, you can upgrade your integration by reinstalling it from the Vercel Marketplace.

      When you finish making selections, click Continue.

   3. Confirm the integration settings. This allows the integration to:

      • Set environment variables for your Vercel project's production, development, and preview environments.
      • Create database branches for preview deployments.
      • Create a development branch for your Vercel development environment.

   4. Click Connect to confirm and proceed with the integration. If you encounter a connection error, see Troubleshoot connection issues.

      After the settings are configured, you are presented with a Success! dialog.

   5. Click Done to complete the installation.

6. To view the results of the integration in Neon:
   1. Navigate to the Neon Console.
   2. Select the project you are connected to.
   3. Select Branches. You will see the primary branch of your project (main). If you created a development branch, you will also see a vercel-dev branch.
7. To view the results of the integration in Vercel:
   1. Navigate to Vercel.
   2. Select the Vercel project you added the integration to.
   3. Select Settings > Environment Variables. You should see the DATABASE_URL variable settings added by the integration.

Use the Neon Vercel Integration

After you add the Neon Vercel Integration to a Vercel project, Neon creates a database branch for each preview deployment. The branch is created when you push commits made on your local branch to your application's source code repository. To see the integration in action, follow these steps:

1. Create a branch in your local source code repository.

   cd myappgit checkout -b myapp-update

2. Make changes to your application on the local branch.

3. Commit the changes. For example:

   git commit -a -m "Update my app"

4. Push your commit to the remote repository:

   git push

   Pushing the commit triggers the following actions:

   • The commit triggers a preview deployment in Vercel, as would occur without the Neon integration.
   • The integration creates a branch in Neon. This branch is an isolated copy-on-write clone of your root branch, with its own dedicated compute endpoint. The branch is created with the same name as your git branch.
   • The integration sets Vercel preview environment variables to connect the preview deployment to the new branch.

Manage Vercel environment variables

The Neon Vercel Integration initially sets the DATABASE_URL environment variable for your Vercel Production and Development environments. When you create a preview deployment, the integration also sets this variable for your Preview environment. If you want to use different Postgres environment variables, the Neon Vercel Integration also supports these variables for defining your database connection:

• PGHOST
• PGUSER
• PGDATABASE
• PGPASSWORD

You can enable these variables from the Neon Console:

1. In the Neon Console, select your project.
2. Select the Integrations page.
3. Find the Vercel integration under the Manage heading, and click Manage.
4. In the Vercel integration drawer, select the environment variables you require. The selected variables will be set in your Vercel project with your next push.

Make the integration available to other Vercel projects

If you added the Neon Vercel Integration to a single Vercel project but would like to make it available for use with your other Vercel projects, complete the steps outlined below.

1. Make sure the Neon Vercel Integration that you added previously has access to the Vercel project that you want to use with the Neon Vercel Integration.
   1. On the Vercel Dashboard, select Integrations.
   2. Find the Neon Postgres integration, and select Manage.
   3. On the Neon Postgres integration page, select Manage Access.
   4. On the Manage Access for Neon Postgres modal, make sure that the Neon Postgres integration has access to the Vercel project. You can do so by selecting Specific Projects and choosing a Vercel project, or by granting access to All Projects. If you previously granted access to All Projects, no change is necessary.
   5. Click Save.
2. Navigate to this URL: https://vercel.com/integrations/neon/new.
3. Follow the prompts. When you reach the Integrate Neon dialog, select the Vercel project that you want to add the integration to. Vercel projects that are already integrated with Neon are identified as CONNECTED, so you'll have to select a different Vercel project.
4. Continue following the prompts to complete the setup. These are the same steps described above, in Add the Neon integration. When you select a Neon project to connect to, be sure to select one that is not already connected to a Vercel project, as you cannot connect one Vercel project to multiple Neon projects or vice versa.

Troubleshoot connection issues

This section describes commonly encountered connection issues for the Neon Vercel Integration.

Failed to set environment variables

If the environment variables configured by the Neon integration already exist, you may encounter the following error due to an existing integration that sets one or more of the same environment variables.

Failed to set environment variables in Vercel. Please make sure that the following environment variables are not set: PGHOST, PGUSER, PGDATABASE, PGPASSWORD, DATABASE_URL

In this case, you can remove or rename the existing environment variables in your Vercel project settings and retry the Neon integration.

1. From the Vercel project page, select Settings.

2. Locate the environment variables required by the Neon integration and remove or rename them.

   note

   Alternatively, you can remove the conflicting integration, assuming it is no longer required. This may be a previous Neon integration or another integration. Removing the integration removes the variables set by the integration.

3. Try adding the Neon integration again. See Add the Neon Vercel Integration.

DATABASE_URL not set on first preview deployment

In earlier versions of the integration, the preview environment DATABASE_URL is not set by the Neon Vercel Integration on the first preview deployment after adding the integration to a Vercel project.

To avoid this issue, you can reinstall the integration to update to the latest version. Alternatively, a workaround is to redeploy your preview deployment in Vercel. The preview environment DATABASE_URL is set on the next deployment. For redeploy instructions, see Managing Deployments, in the Vercel documentation.

Manage the Neon Postgres integration in Vercel

To view permissions, manage which Vercel projects your integration has access to, or uninstall the Neon integration:

1. On the Vercel dashboard, select Settings > Integrations.

2. Find the Neon integration and select Configure.

   note

   Removing the Neon Vercel Integration removes the Vercel environment variables set by the integration. It does not remove Neon branches created by the integration. To remove Neon branches, see Delete a branch.