Email via Resend (mail-resend)

Delivers the emails your app sends (password resets, notifications) through the Resend HTTP API. No SDK: one fetch call.

npx calm add mail-resend

Set RESEND_API_KEY and MAIL_FROM, a sender on a domain you verified in Resend. MAIL_FROM takes precedence over mail.from in calm.config.js.

In development without a key, the block stays inactive and emails keep going to the devtools Mail panel. In production without a key, calm doctor reports an error.

Sending email#

Everything goes through app.mailer, so your code does not depend on the provider:

await ctx.app.mailer.send({
  to: 'ada@example.com',
  subject: 'Your invoice',
  text: 'Thanks for your order.',
  html: '<p>Thanks for your order.</p>',
});

to can be one address or an array. A failed delivery throws with Resend's status and message. For retries, send from a job.

Without a mail block#

The built-in transport only works in development: it prints a short notice and hands the message to devtools. In production with no transport, emails are not sent and an error is logged, and calm doctor --prod warns about it. You can also register your own transport in a plugin:

calm.mailer.use({
  name: 'my-provider',
  async send({ to, from, subject, text, html }) { /* deliver it */ },
});