Inviting users and assigning them to nuki devices

I am looking for all the API’s that are needed to create a user account, Delete a user account, assigning a user a permission for a specific Lock and unassigning them.

Anybody can help me where to find them?

I want to sync NUKI accounts from a Azure Active Directory user group

You can take a look at

for a start.
I assume you already checked in general?

Did you manage to create a good integration with Active Directory?
Did you find and open source or commercial solution to automate release and revokation of keys?