Edge Handlers overview

This feature is in early access BETA.

Edge Handlers are powerful scripts that run directly from our CDN edge nodes. They allow you to dynamically affect traffic to and from your site and personalize your visitors' site experience through programmable routing. Edge Handlers can:

  • filter incoming HTTP requests
  • manipulate HTTP requests and responses

To get started using Edge Handlers, visit our sign-up form to request an early access invitation.

Manage your Edge Handlers

Netlify Edge Handler deploys are immutable. This means that an update to a handler on your production branch won’t affect the version deployed in a branch deploy or in a Deploy Preview.

To access versions of your Edge Handlers in the Netlify UI, select your site from the Sites menu, then go to the Edge Handlers tab.

By default, the list displays the handlers in the current production deploy. To find Edge Handlers on another deploy, use the dropdown at the top of the list. You can start typing to jump to a particular branch.

Limitations

Keep the following considerations in mind when working with Edge Handlers.

Operation limits

By default, Edge Handlers have limits for the amount of memory and execution time they can use:

  • memory limit: 256 megabytes
  • execution time limit: 50 milliseconds

An Edge Handler may run up against the memory limit, for example, while transforming a large response body. If a handler goes over a limit, it will terminate abruptly, and the request will fail to complete. If you want additional memory and execution time to run your Edge Handlers, please contact sales.

Bundled dependencies

Within Edge Handler code, dynamic import statements for dependencies aren't allowed. You can't include dependencies at run time, and your code must be completely isolated before Netlify runs it. All dependencies must be bundled inside the Edge Handler before the artifact is deployed to our edge nodes.