SMTP

The SMTP transport is an official Better-Notify package backed by Nodemailer. Use it when your provider gives you SMTP credentials and you want a straightforward way to send Better-Notify email routes.

It is a thin delivery adapter. Better-Notify handles rendering and validation upstream; smtpTransport() only turns the rendered email into a Nodemailer sendMail() call.

Install

npm install @betternotify/smtp @betternotify/core @betternotify/email

Usage

import { createNotify, createClient } from '@betternotify/core';
import { emailChannel } from '@betternotify/email';
import { smtpTransport } from '@betternotify/smtp';

const email = emailChannel({
  defaults: { from: { name: 'My App', email: 'noreply@example.com' } },
});

const rpc = createNotify({ channels: { email } });
const catalog = rpc.catalog({
  /* routes */
});

const mail = createClient({
  catalog,
  transportsByChannel: {
    email: smtpTransport({
      host: 'smtp.example.com',
      port: 587,
      auth: {
        user: process.env.SMTP_USER!,
        pass: process.env.SMTP_PASS!,
      },
    }),
  },
});

For implicit TLS on port 465, set secure: true:

import { smtpTransport } from '@betternotify/smtp';

const transport = smtpTransport({
  host: 'smtp.example.com',
  port: 465,
  secure: true,
  auth: {
    user: process.env.SMTP_USER!,
    pass: process.env.SMTP_PASS!,
  },
});

Common options

From address behavior

If message.from is missing, the transport falls back to auth.user. If neither is set, Better-Notify throws a CONFIG error.

Some SMTP providers rewrite the From address to match the authenticated user. When that happens, Better-Notify logs a one-time warning for each mismatching address. If you want the visible sender to stay unchanged, align defaults.from with auth.user or switch to a provider that accepts your verified sender address as-is.

Sending limits

SMTP is a thin transport. It does not rate-limit, retry, or fail over for you.

Before using it in production, check your provider's limits for:

• sends per second or minute
• daily volume
• concurrent connections
• sandbox or trial restrictions

If you need throttling or provider fallback, add middleware such as withRateLimit or wrap SMTP in multiTransport({ strategy: 'failover' }).