Squarespace is a website builder with commerce and a built-in Email Campaigns product. It's a more closed ecosystem than Shopify, with order confirmations sent natively.
Squarespace Commerce is closed; pair with MailKite for off-platform transactional flows via API.
A minimal, copy-paste starter. Swap in your own domain and API key.
import { MailKiteClient } from "@mailkite/client";
// One API, your own DKIM-signed domain — no mail server to run
const mailkite = new MailKiteClient({ token: process.env.MK_API_KEY! });
await mailkite.send({
from: "you@yourdomain.com", // any address on a verified domain
to: "user@example.com",
subject: "Hello from Squarespace",
html: "<p>Sent in milliseconds via MailKite.</p>",
});Point a domain, set one SMTP endpoint, send your first email in minutes. Unlimited domains, no credit card.