Marketing automation

Customer.io

Lifecycle/behavioral messaging.

Email capabilities

  • Own email API
  • Sends notifications
  • Webhooks

Connection methods

  • API
  • Webhook

Customer.io is a lifecycle and behavioral messaging platform (email, SMS, push, in-app) with a developer-friendly Send API, Liquid templating, and server SDKs. Popular for SaaS lifecycle.

Connect Customer.io to MailKite

Use Customer.io for lifecycle and MailKite for inbound + raw transactional.

Receive email into Customer.io via MailKite

A minimal, copy-paste starter. Swap in your own domain and API key.

webhook.ts
import { verifyWebhook } from "@mailkite/client";

// MailKite POSTs every inbound email at your domain as JSON.
// Point a route at this handler in the MailKite dashboard.
export default async function handler(req: Request) {
const raw = await req.text();
const sig = req.headers.get("x-mailkite-signature") ?? "";

// Reject anything not signed by your webhook secret
const ok = await verifyWebhook(sig, raw, process.env.MK_WEBHOOK_SECRET!);
if (!ok) return new Response("bad signature", { status: 401 });

const email = JSON.parse(raw);
// Route into Customer.io: open a ticket, create a task, store a record
await routeIntoName(email); // email.from · email.subject · email.text

return new Response(JSON.stringify({ ok: true }));
}
Read the inbound webhooks guide
Email tools

Commonly paired with Customer.io

Connect Customer.io to MailKite today

Point a domain, set one SMTP endpoint, send your first email in minutes. Unlimited domains, no credit card.