Does Gandi provide a dynamic DNS service?
You want to add a nameserver to your domain, using a dynamic IP service. Gandi does not provide and does not plan to provide a dyndns service. Nonetheless, you can use Gandi as registrar and use a third-party dyndns service for your domain. You just need to state DNS you want to use (for example DNS from dyndns.org) exactly as you would do for any webhosting company.