Kong Dev Portal - Call External API

Hi Community,
We are using Kong Dev Portal and wanted to notify a third party system when a user registers. Is there a way the dev portal can be customised to call an external API based on certain user action? If yes, any sample example or reference docs will be helpful.
We are using : GitHub - Kong/kong-portal-templates: Themes, components, and utilities to help you get started with the Kong Dev Portal.

I have went thru the Kong Documentation for dev portal but could not find any related references. Developer Portal Structure and File Types - v2.5.x | Kong Docs

Any help would be appreciated. Thanks in advance.