Vercel

This topic explains how to use the LaunchDarkly Vercel integration. This integration enables flag evaluation within Vercel Functions. It writes the latest flag data from your configured environment directly to a Vercel Global Config in your account, and syncs later flag or segment changes to that Global Config automatically.

This integration does not connect LaunchDarkly SDK keys to your Vercel projects. If you want SDK keys provisioned and synced automatically as environment variables, read Vercel Marketplace instead.

You can use the Vercel integration to bootstrap your application with the latest client-side feature flags. This eliminates the initial remote call to LaunchDarkly, providing zero-latency client-side feature flags with no flash of original content or shift in content layout. Evaluating flags within Vercel Functions gives you the same benefit at the server level, without added latency from network requests.

Vercel enforces size limits on Global Config values. Additionally, Vercel charges customers for Vercel Config writes. Each feature flag or segment change in an environment where the integration is installed will incur a Global Config write. Based on these limits, Vercel Enterprise customers and Vercel Pro customers with moderately-sized environments are likely to benefit the most from this integration. To learn more, read Vercel’s documentation on Global Config limits and pricing.

Install a Vercel integration

For the Vercel integration to work, you need a Vercel account with at least one project.

You can install a Vercel integration on the LaunchDarkly page in the Vercel integrations marketplace.

To install a Vercel integration for your environment:

1. Navigate to Vercel’s Integrations page for LaunchDarkly.

2. Click Add Integration.

3. Select the Vercel account that you would like to connect to LaunchDarkly.

4. Choose the projects within that account that you would like LaunchDarkly to have access to.

5. Click Continue.

6. Review the permissions that this integration requires. Then click Add Integration. The LaunchDarkly configuration screen appears:

   

7. Click Authorize to grant access to the LaunchDarkly integration.

8. Enter a Name for the integration. This integration is specific to this combination of your LaunchDarkly environment and the Vercel Global Config ID.

9. Choose an environment from the Environment menu. Your data appears in your Global Config under the key LD-Env-{{environment client-side ID}}.

10. Choose a Global Config from the Global Config menu. Alternatively, click Click to create new global config to create a new global config.

11. Click Save configuration.

    

Configure the LaunchDarkly Vercel integration

You can manage existing Vercel integrations from the same LaunchDarkly listing page in the Vercel integrations marketplace.

To manage an existing Vercel integration:

1. In Vercel, navigate to the Integrations page.

2. Find your LaunchDarkly integration and click Manage.

3. Click Configure. The LaunchDarkly configuration panel appears.

   

4. Click Edit to modify the integration. You can change the configuration name or select another Global Config destination to export to.

5. Click Save.

Uninstall the LaunchDarkly Vercel integration

To uninstall an existing Vercel integration:

1. Navigate to the Integrations page in Vercel.

2. Find your LaunchDarkly integration and click Manage.

3. Click Configure. The LaunchDarkly configuration panel appears.

   

4. Click Delete to remove each integration configuration.

5. Return to the Vercel integration page.

6. Click Remove Integration.