Use these integrations to deliver HTML and plain text rendered by @unlayer/react-elements. Each provider receives the same transactional invoice message. Pass the rendered html string, including its head styles, to the provider; the provider does not need to render the React tree again.

The snippets below are complete files in src/providers. They import src/message.ts and src/invoice.tsx. From the repository root:

pnpm install
pnpm build
pnpm --filter @unlayer/content-workflows-example render:email

Inspect the output before running a send command. Every send:* command sends one real email. Export a verified sender address and a recipient you control:

export EMAIL_FROM='receipts@your-verified-domain.com'
export EMAIL_TO='your-test-inbox@example.com'

Replace both addresses. Set the provider-specific variables below in the process environment or your deployment's secret manager. The scripts do not load .env files automatically. No credentials belong in browser code. For standalone use, install @unlayer/react-elements react react-dom, add tsx to dev dependencies, set "type": "module" and "jsx": "react-jsx", and copy the shared files plus your chosen provider file. Then use npx tsx src/providers/<provider>.ts.

SDK errors are allowed to fail the process; Resend's returned error is explicitly thrown. A successful ID/status means the provider accepted the request, not that the recipient received it. Use provider events for delivery/bounce tracking and application-level deduplication for retries.

Install in your own project: npm install resend. The workspace example already declares this dependency.

Set RESEND_API_KEY. Requires an API key and a verified sending domain. Resend Node.js setup.

import { Resend } from "resend";
import { deliveryMessage, requireEnv } from "../message";

const client = new Resend(requireEnv("RESEND_API_KEY"));
const { data, error } = await client.emails.send(deliveryMessage());
if (error) throw new Error(`Resend: ${error.message}`);
console.log("Resend accepted:", data?.id);

pnpm --filter @unlayer/content-workflows-example send:resend

Expected: Resend accepted: <id>.

Install in your own project: npm install @aws-sdk/client-sesv2. The workspace example already declares this dependency.

Set AWS_REGION. Use the AWS SDK default credential chain (for example an IAM role or AWS_PROFILE) with permission to send via SES. Set AWS_REGION to the region containing your verified identity. In the SES sandbox, recipients also need verification. SES SendEmail API.

import { SESv2Client, SendEmailCommand } from "@aws-sdk/client-sesv2";
import { deliveryMessage, requireEnv } from "../message";

const client = new SESv2Client({ region: requireEnv("AWS_REGION") });
const { from, to, subject, html, text } = deliveryMessage();
try {
  const result = await client.send(new SendEmailCommand({
    FromEmailAddress: from,
    Destination: { ToAddresses: [to] },
    Content: {
      Simple: {
        Subject: { Data: subject, Charset: "UTF-8" },
        Body: {
          Html: { Data: html, Charset: "UTF-8" },
          Text: { Data: text, Charset: "UTF-8" },
        },
      },
    },
  }));
  console.log("SES accepted:", result.MessageId);
} finally {
  client.destroy();
}

pnpm --filter @unlayer/content-workflows-example send:ses

Expected: SES accepted: <MessageId>.

Install in your own project: npm install postmark. The workspace example already declares this dependency.

Set POSTMARK_SERVER_TOKEN. Use a server token and a confirmed sender signature/domain. The outbound message stream is for transactional mail. Postmark sending API.

import { ServerClient } from "postmark";
import { deliveryMessage, requireEnv } from "../message";

const client = new ServerClient(requireEnv("POSTMARK_SERVER_TOKEN"));
const { from, to, subject, html, text } = deliveryMessage();
const result = await client.sendEmail({
  From: from,
  To: to,
  Subject: subject,
  HtmlBody: html,
  TextBody: text,
  MessageStream: "outbound",
});
console.log("Postmark accepted:", result.MessageID);

pnpm --filter @unlayer/content-workflows-example send:postmark

Expected: Postmark accepted: <MessageID>.

Install in your own project: npm install @sendgrid/mail. The workspace example already declares this dependency.

Set SENDGRID_API_KEY. Use an API key with Mail Send permission and an authenticated sender. SendGrid Node.js SDK.

import sendgrid from "@sendgrid/mail";
import { deliveryMessage, requireEnv } from "../message";

sendgrid.setApiKey(requireEnv("SENDGRID_API_KEY"));
const [response] = await sendgrid.send(deliveryMessage());
console.log("SendGrid accepted:", response.statusCode, response.headers["x-message-id"]);

pnpm --filter @unlayer/content-workflows-example send:sendgrid

Expected: SendGrid accepted: 202 <x-message-id>.

Install in your own project: npm install nodemailer. For TypeScript, also install npm install --save-dev @types/nodemailer. The workspace example already declares this dependency.

Set SMTP_HOST, SMTP_PORT, SMTP_USER, SMTP_PASSWORD. Use credentials issued by your SMTP service. Port 465 uses implicit TLS; submission ports such as 587 use required STARTTLS here. Keep certificate verification enabled. Nodemailer SMTP options.

import nodemailer from "nodemailer";
import { deliveryMessage, requireEnv } from "../message";

const port = Number(requireEnv("SMTP_PORT"));
if (!Number.isInteger(port) || port < 1 || port > 65535) {
  throw new Error("SMTP_PORT must be an integer between 1 and 65535");
}
const transport = nodemailer.createTransport({
  host: requireEnv("SMTP_HOST"),
  port,
  secure: port === 465,
  requireTLS: port !== 465,
  auth: { user: requireEnv("SMTP_USER"), pass: requireEnv("SMTP_PASSWORD") },
});
try {
  const result = await transport.sendMail(deliveryMessage());
  if (result.rejected.length) throw new Error("SMTP rejected the recipient");
  console.log("SMTP accepted:", result.messageId);
} finally {
  transport.close();
}

pnpm --filter @unlayer/content-workflows-example send:nodemailer

Expected: SMTP accepted: <messageId>.

For PDF attachments, first generate bytes with the Playwright guide, then follow your provider's attachment API and size limits. Design JSON is for the visual editor, not an email body.