Forwarding

When Mailcast receives an email sent to an alias, it can forward it to another email address you specify.

Each alias can have multiple forward destinations.

Destination addresses

The simplest way to forward an email is to specify a simple email address.

alias@mydomain.com → mydomain@gmail.com

You can also use parts of the email address when specifying the destination.

*@mydomain.com → mydomain+{user}@gmail.com

will be processed as:

john@mydomain.com → mydomain+john@gmail.com

{local_part} is replaced with everything before the @ symbol.
{user} is replaced with the user part of the email address (everything before the + symbol, if it is present).
{tag} is replaced with everything after the + symbol, if it is present.
{subdomain} is replaced with the subdomain part of the email address, if Subdomain receiving is enabled.

Regular expression substitution

If you use a regular expression alias, then you can use positional and named captures in the forwarding target.

Example named capture forwarding target:

/regex-(?<name>.+)/@mydomain.com → user+{name}@gmail.com

If the email was sent to regex-foo@mydomain.com, then the forwarding target will be user+foo@gmail.com.

Example positional capture forwarding target:

/regex-(\w+)/@mydomain.com → user+{$1}@gmail.com

If the email was sent to regex-foo@mydomain.com, then the forwarding target will be user+foo@gmail.com.

DKIM, SPF, DMARC, and ARC

When email is received, Mailcast will check the DKIM, SPF, and DMARC policies of the email. If the email passes these checks, Mailcast will add an ARC chain header to the forwarded email and then send the email on to the email address you specified.