Build MIME from parts Written by the Hub
A MIME builder, for senders that would otherwise assemble multipart messages by hand.
In detail
Our exporter already produces MIME, so the tool is not on our path. It is listed because the failure it prevents is a real one: hand-built multipart messages with wrong boundaries or missing headers are a recurring source of "the message looks broken at the receiver", and any customer assembling MIME themselves is a candidate for that problem.