SMTP

Anything that can send email over SMTP can send through Herald without code changes: point its settings at Herald and use an API key as the password.

Herald only accepts authentication over TLS, so an app can’t send its key in the clear by mistake.

As a URL

Many apps take one setting:

SMTP_URL=smtps://herald:hrld_live_…@smtp.heraldmail.dev:465

Nodemailer

import nodemailer from 'nodemailer'

const transport = nodemailer.createTransport({
  host: 'smtp.heraldmail.dev',
  port: 465,
  secure: true,
  auth: { user: 'herald', pass: process.env.HERALD_API_KEY },
})

await transport.sendMail({
  from: 'Hallelo <hello@hallelo.church>',
  to: 'ada@example.com',
  subject: 'This Sunday',
  text: 'Doors open at 10.',
})

Herald’s own headers

Herald reads these, then removes them before the message goes on:

Everything else is handled as it is for the API: the same checks on the sender’s domain, the same quota and suppressions, and the same log and webhooks. A message Herald refuses is refused in the SMTP conversation, with the reason.