What it sends
Every message on Emails we send: booking confirmations and moved-appointment notices, invoices, receipts, quotes, app logins. Each is a template the engine fills in; there is nothing to edit in Resend itself. The engine sends no operator email: problems reach the owner through Sentry.Sender addresses
All three are on the comforthub.ca domain, which is verified in Resend so mail is signed and lands in inboxes. Replies to a customer email go to the address it came from.
The safety guard
Before any message leaves, the address is checked against a short allowlist and anything else is redirected to the owner; the rule and how to widen it are on Email safety.The ledger
Every send is one row in a table on our side, written before the message leaves and completed with Resend’s message id after. One live row per email per record, so a booking is never confirmed twice; a resend has to be asked for on purpose. The row is the proof a message went: it holds the recipient, the subject, the time, and the id Resend gave it.Limits worth knowing
- The key the engine holds can only send. Reading a sent message back out of Resend needs a wider key, which the engine does not have on purpose.