Custom provider with overwrite or re-use of azurerm code

All, we have an API in house which generates keys for HSM. Terraform doesn’t like this since its not the default. I can write a custom provider just fine for that part. Only the read/update/delete actions we can still use that as a normal keyvault action. Is there a way i can just tell my custom provider to use it from azurerm somehow? Looking at this i would like to use the read/update/delete from that in my own custom provider. Or i would like to overwrite the create from the keyvault from azure? Don’t know whats the best course of action. Just copying over the code seems like not nice and complex. Thanks for any tips/pointers.

never mind, build it, finished it.