In addition to the previously existing functionality of sending email(s) when an application is ready to review, now you can also (or alternatively) send a webhook. From the readme:

This feature lets you specify a webhook url and payload that is fired when an application is ready for review. The payload is a dict that is defined in the config file. You can use variable substitution in specified fields of your payload to help support properly formatting things like message bodies. The full list of variable substitutions is documented in the config file.

It might not be desirable to do this substitution for all fields of the payload, so only fields that you specify will be formatted in this way. Add any fields you want to do variable substitution for to the webhook_format_fields list in the config file.

Upgrade notes

You probably want to rework your email templates if you previously set them up. Some variable names changed in the new email templates to make it easier to share variables across both the email and webhook functionality.