Webhook for Mayan

I want to ask if there is webhook built-in Mayan or anyone has experience on doing it?

So far, I know that there is only REST API available. But in my case, the webhook would be much better solution. I want to send SMS to related users when a workflow is completed or a new document with specific tag was uploaded.

I guess you are looking for the http request action that you can use in workflows. It allows you to execute a GET or POST request to a remote server. I use this myself and it works very well.

Please have a look at: Workflows — Mayan EDMS 4.4.8 documentation

Thank you. Your suggestion is great for workflow. But for the case new document is uploaded, do you have any idea how I can send SMS to the user/manager?

You could just start a workflow automatically once the document is uploaded and trigger the action in the initial workflow state. The name workflow might be a bit misleading in that case, but this is the way it can be done in Mayan.