Vercel incident: Increased Function Invocation Errors - ERR_MODULE_NOT_FOUND

Affected components

• Edge Functions

1. resolvedMay 18, 2026, 23:52 UTC

   This incident has been resolved. Some deployments created between May 18, 2026, 06:15 PM - 10:16 PM UTC may have experienced increased ERR_MODULE_NOT_FOUND function invocation errors due to a bad rollout. Deployments created outside of this window are unaffected. The fix is being rolled out to existing deployments retrospectively and is expected to finish in the next few hours.

2. monitoringMay 18, 2026, 22:19 UTC

   We are continuing to monitor for any further issues.

3. monitoringMay 18, 2026, 22:16 UTC

   A fix is rolled out for the function invocation errors affecting React Router 7 deployments. To recover, redeploy your application or use Instant Rollback to a previous deployment from the dashboard. We're continuing to monitor.

4. identifiedMay 18, 2026, 22:11 UTC

   We're continuing to work on rolling out a fix. In the mean time, customers may use Instant Rollback to a previous deployment version as an immediate workaround in order to recover.

5. identifiedMay 18, 2026, 21:53 UTC

   The issue has been identified and a fix is being implemented.

6. investigatingMay 18, 2026, 21:42 UTC

   We're investigating an issue where customers are currently experiencing application failures due to function invocation errors when using React Router 7.

What APIStatus.watch saw

Our 5-minute checks didn't record a change in Vercel's overall status around this incident. Smaller or regional incidents often leave a provider's overall status green.

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How often does Vercel have incidents?

Vercel reported 24 incidents in the last 90 days, 10 of them major or critical. A typical incident lasted 59 min. See Vercel's uptime and incident history