@xlambda-tech/email

Send email from your own domain, and — the reason this package exists — turn on receiving with almost no glue code.

Receiving inbound mail

import { createInboundHandler } from '@xlambda-tech/email';

export const { POST } = createInboundHandler({
  secret: process.env.XLAMBDA_WEBHOOK_SECRET!,
  onReceived: async (msg) => {
    // msg is fully typed: domain, from, to, subject, textBody, htmlBody, headers, sizeBytes, truncated
    await db.inboundEmails.create({ data: msg });
  },
}).toNextRouteHandler();

That's the whole integration for a Next.js App Router route handler. Point your project's webhookUrl (dashboard → Settings → Webhooks) at this endpoint and inbound mail on your managed domain starts landing in your own database.

This is the only place a message's body ever exists. The platform stores no message content server-side by design — only metadata (from, to, subject, size) shows up in client.domains.messages(). If your handler doesn't persist what it needs on receipt, it's gone (deliveries do retry 3× with exponential backoff if your endpoint errors, so a transient failure isn't fatal — a onReceived that never runs at all is).

Other frameworks:

import { toExpressHandler } from '@xlambda-tech/core/webhooks/adapters/express';
import { toFastifyPlugin } from '@xlambda-tech/core/webhooks/adapters/fastify';

// Express - MUST be mounted behind express.raw(), not express.json()
app.post('/webhooks/email', express.raw({ type: 'application/json' }), toExpressHandler(handler));

// Fastify - registers its own route + raw-body content-type parser, scoped to this plugin only
fastify.register(toFastifyPlugin(handler), { prefix: '/webhooks/email' });

// Raw Node http
const server = http.createServer(handler.toNodeHandler());

onSent/onDelivered/onBounced are also available on createInboundHandler for the outbound-side events, if you want one endpoint handling everything.

Sending

import { EmailClient } from '@xlambda-tech/email';

const client = new EmailClient({ apiKey: process.env.XLAMBDA_API_KEY! });

await client.emails.send({
  from: '[email protected]',
  to: '[email protected]',
  subject: 'Hello',
  html: '<p>Hi there</p>',
});

Resend-compatible shape (from/to/cc/bcc/replyTo/subject/text/html). from's domain must belong to a domain your project owns and has verified.

Setting up a domain

const domain = await client.domains.create({ projectId, domain: 'yourdomain.com' });
// domain.dkimRecords -> publish these at your DNS registrar
await client.domains.verify(domain.id); // re-checks MX/SPF/DKIM/DMARC once published

Checking message history

const { messages } = await client.domains.messages(domain.id, { direction: 'received', limit: 50 });

Metadata only (from/to/subject/status/size) — for the full body of a received message, you must have captured it via createInboundHandler at receipt time (see above).