smtp_generic_maps = hash:/etc/postfix/generic

root@system.fqdn noreply@company.com
www-data@system.fqdn noreply@company.com

postmap /etc/postfix/generic

$ vim /etc/email-addresses

root: noreply@example.com
www-data: noreply@example.com

$ vim /etc/passwd

root:x:0:0:Example Company:/root:/bin/bash
www-data:x:33:33:Example Company:/var/www:/usr/bin/nologin