Delivery notifications
How a recipient learns mail arrived, gated by their notification preferences, including the held-pending to delivered release that fires when a previously-unreachable recipient signs up.
A recipient is notified whenever mail becomes deliverable to them. The trigger is the delivery transition, not merely the moment a sender first pushed the item, which is what makes Keepable's held-pending promise work.
The ordinary case
When a sender delivers content to a registered recipient, the item lands in their inbox and a notification is enqueued through the recipient's preferred channels (email and push). Notifications are gated by the recipient's notification preferences and a suppression list, so a recipient who has muted a category does not hear about it, and email notifications route to the recipient's verified email (see Email verification).
Held-pending to delivered
A sender can address content to someone who is not on Keepable yet. Rather than
bounce, Keepable holds that item pending registration (the sender sees a
retained status; see Send content). Nothing is
lost: the item waits.
When that person finally arrives, the held item is resolved and released into their inbox:
A sender addresses content to an identifier (for example an email) that does not yet resolve to a recipient. Keepable holds it pending registration.
The person signs up, or verifies the email that the content was addressed to. That identifier becomes resolvable.
Keepable releases every item held for that now-resolvable identifier into the recipient's inbox, and notifies them, exactly as it would for a fresh delivery.
This is why the notification trigger is the transition to deliverable, not first ingest: a recipient who registers must learn that mail was waiting for them, not just hear about mail that arrives afterward.
Verifying an email is one of the events that can release held content. The moment an email is verified and linked it resolves, and any item a sender addressed to it while the recipient was unreachable is delivered and announced. See Email verification.
Preferences
Recipients control which notifications they receive per channel (email and push) across categories such as new letters, unread reminders, and product news. Delivery notifications respect those preferences and the suppression list, so the surface never sends a recipient something they have opted out of.