WildCard Let'sEncrypt

Hi! How to use LetsEncrypt wildcard for subdomains.

https://gorails.com/guides/free-ssl-with-rails-and-nginx-using-let-s-encrypt

+1 from me. Or if you don't have the bandwidth or you don't think this is enough of a priority (multi-tenant apps aren't popular enough from developers) - an alternative for wildcard certs would be appreciated!