Synchronisation with Nextcloud Contacts

Your software
My Mautic version is: 4.4.10
My PHP version is:8.0.30
My Database type and version is:10.6

Ist it possible to synchronize Nextcloud with Mautic. I have all my contacts wie Cardav/Caldav synchronized with the Nextcloud and it would be nice if new contacts in Mautic would transfered to the Nextcloud.

If your question is - is there a plugin? No.
Can you sync with your own code? Yes.

Sounds nice - but i’m not a programmer.
is there somewhere a tutorial how it works?

Can anyone help me to connect Nextcloud with Mautic?

I found this here:
Standard OpenAPI App. Seems looking good. Anyone a knowledge if i can connect Mautic with this?