Need to hire API help for CB User Sync with 3rd party application

I am using a 3rd party application that does have a API kit for user sync. This 3rd party application is the main database, and I would like their database to send their latest users to my CB user database on a nightly basis.

My custom CB fields already match the 3rd parties. I am looking to contract out someone who has experience with CP APIs and REST.

Thanks

You should be able to use CB Auto Actions for that. We don't have any REST endpoints yet, but will eventually exclusively for Joomla 4 and onwards since Joomla 4 now provides web services. For now you can create your own REST endpoints using CB Auto Actions. As long as your external database has a reference to their Joomla user id you can update them easily using a Field auto action. You can even register them externally using a Registration auto action. CB Auto Actions even supports JSON response so you can send a request and respond with a JSON response of whatever you like.