At ZEIT, we rely heavily on customer feedback to guide our work. In the recent times, our customers have pointed out opportunities to improve on our error pages.
Today, we are thrilled to introduce improved error pages on the entire ZEIT Now platform.




The new error pages clearly distinguish between application errors and platform errors.



Application Vs. Infrastructure Errors

When a customer encounters an error on a ZEIT hosted application, it could be because:
  • An error was thrown by the application itself
  • An infrastructure component of Now encountered an error
Therefore, we now make a conscious effort to distinguish between the two types of errors.

502 — Bad Gateway

Application Errors
One of the most common errors on the ZEIT platform is NO_STATUS_CODE_FROM_LAMBDA, which happens when an unhandled exception is thrown by the application.



An application-caused 502 Bad Gateway error being presented with the new error pages.

Platform Errors
If a 502 error is caused by the platform (e.g INTERNAL_STATIC_REQUEST_FAILED), the error page uses the Platform Error version.



A platform-caused 502 Bad Gateway error being presented with the new error pages.

404 — Not Found

Previously, when an end-customer encountered a 404 error, it wasn't clear whether the error was due to a missing path in the application, or due to a deployment that didn't exist on our platform.
Missing Path
If a 404 error is caused by a path missing in the application, the error page uses the Application Error version with the error code FILE_NOT_FOUND.



An application-caused 404 Not Found error being presented with the new error pages.

Deployment Not Found
If a 404 error is caused by a missing deployment on the Now platform, the error page makes it clear with the error code DEPLOYMENT_NOT_FOUND.



A missing deployment 404 Not Found error being presented with the new error pages.

503 — Service Unavailable

When a 503 error takes place (e.g V1_NO_SCALED_DEPLOYMENTS due to overloaded V1 deployment replicas when maxScale is set to 1), we now make it clear on the error page, along with hints to fix the error.



A 503 Service Unavailable error being presented with the new error pages.

General Highlights and Conclusion

We are confident that the updates to our error pages will improve the debugging experience for project developers, as well as end-customers when they encounter errors.
To summarise, the updates made to all error pages include:
  • New, fresh design that highlights the important information
  • Clear distinction between application and platform errors
  • Unique ID for every error, for debugging purposes
  • Clearer display of the error type and code
  • Helpful hints for both end-customers and project owners towards mitigating the error
We would love to hear your thoughts on our new error pages! If you'd like to share feedback, ask questions, or just say hi, you can reach out to us over Twitter or Chat.