Send email from your app

Apps have no built-in mailer and SMTP is blocked; send through Resend over HTTP with your own key.

Your app has no built-in mailer. Outbound SMTP ports (25, 465, 587) are blocked, so apps send mail through an HTTP email service such as Resend, with your own key.

How to set it up

1. Create a Resend account and verify a sender domain you control.
2. Ask your builder to store your key as a Secret. Never put it in code.
3. Ask for the emails you want: invites, receipts, digests.

Your builder validates recipient addresses before sending. Bounced spam burns your domain, so keep lists clean.

There is no inbox path into <slug>.outer.now. Receiving mail needs a service in front that forwards to your app as HTTP.

For the technical detail, your builder reads Send email with Resend.