What is an ALIAS record?
An ALIAS record is a virtual record type that we created to provide CNAME-like behavior on apex domains.
For example, if your domain is example.com and you want it to point to a host name like
myapp.herokuapp.com, then you cannot use a CNAME record, but you can use an ALIAS record. The ALIAS record will automatically resolve your domain to one or more A records at resolution time and thus resolvers see your domain simply as if it had A records.