Cloudflare Workers

Send your first email from a Cloudflare Worker using the mailblastr SDK. The SDK uses the standard fetch API and runs without modification on the Workers edge runtime — install it with npm install mailblastr.

Prerequisites

Before you start, you will need:

• A MailBlastr API key.
• A verified domain to send from.
• A Cloudflare Worker — recommended to bootstrap with npm create cloudflare.

1. Install the SDK

npm install mailblastr

2. Store your API key as a secret

Add your API key as an encrypted Worker secret so it is never committed to source.

npx wrangler secret put MAILBLASTR_API_KEY
# paste mb_xxxxxxxxx when prompted

3. Send the email from your Worker

In your Worker's fetch handler, read the key from env, instantiate the SDK client, and call mb.emails.send().

import { MailBlastr } from 'mailblastr';

export default {
  async fetch(request, env, ctx): Promise<Response> {
    const mb = new MailBlastr(env.MAILBLASTR_API_KEY);
    const { data, error } = await mb.emails.send({
      from: 'Acme <onboarding@yourdomain.com>',
      to: ['delivered@example.com'],
      subject: 'hello world',
      html: '<strong>it works!</strong>',
    });

    return Response.json(error ? { error } : { data }, {
      status: error ? 500 : 200,
    });
  },
} satisfies ExportedHandler<{ MAILBLASTR_API_KEY: string }>;

4. Deploy and send email

Run wrangler deploy and wait for it to finish. It will give you a URL like https://my-worker.your-name.workers.dev that you can open to verify the email was sent.