Docker registry v2 with custom S3 service

Hello

Is there any way to set up docker registry v2 with a different S3 service than Amazon AWS?
I could set up version 1 against a custom S3 server with -e AWS_HOST=custom.s3.com option and it was working fine.

In registry version 2 I cannot find such an option / variable where I could direct the registry to different service.

Thanks!