Access is invite-only during beta. Once invited, create a key to personalize these examples. Production sending requires a separate review.
Inbox forwarding
Inbound mail is resigned and sent to an address on a sending domain.
Set forward_to on an inbox to an address on a verified sending domain you own. When mail lands, PostShiba stores it (and posts the webhook if one is set), then composes a new outbound message signed with that domain's DKIM so the forwarded copy authenticates.
The From on the forwarded copy is {mailbox}@{sending_domain}. Reply-To is the original sender. The destination cannot be this inbox's receive host or another inbox, which would loop.
Forwarding uses a sending-ready cluster and a live credential for the domain's tenant. Until the team is approved, forward_to is treated as a self-send address so the copy can leave. Over the cluster send cap, the forward is retried.
Leave forward_to blank to store and webhook only. The dashboard can change it after create. The API sets it on create.