Customer.io Core Features

Overview

Implement Customer.io's key platform features: transactional emails/push (password resets, receipts), API-triggered broadcasts (one-to-many on demand), segment-driving attributes, anonymous-to-known user merging, and person suppression/deletion.

Prerequisites

• customerio-node installed
• Track API credentials (CUSTOMERIO_SITE_ID + CUSTOMERIO_TRACK_API_KEY)
• App API credential (CUSTOMERIO_APP_API_KEY) — required for transactional + broadcasts

Instructions

Feature 1: Transactional Email

Transactional messages are opt-in-implied messages (receipts, password resets). Create the template in Customer.io dashboard first, then call the API with data.

// lib/customerio-transactional.ts
import { APIClient, SendEmailRequest, RegionUS } from "customerio-node";

const api = new APIClient(process.env.CUSTOMERIO_APP_API_KEY!, {
  region: RegionUS,
});

// Send a transactional email
// transactional_message_id comes from the Customer.io dashboard template
async function sendPasswordReset(email: string, userId: string, resetUrl: string) {
  const request = new SendEmailRequest({
    to: email,
    transactional_message_id: "3",  // Template ID from dashboard
    message_data: {
      reset_url: resetUrl,
      expiry_hours: 24,
      support_email: "[email protected]",
    },
    identifiers: { id: userId },    // Links delivery metrics to user profile
  });

  const response = await api.sendEmail(request);
  // response = { delivery_id: "abc123", queued_at: 1704067200 }
  return response;
}

// Send an order confirmation with complex data
async function sendOrderConfirmation(
  email: string,
  userId: string,
  order: { id: string; items: { name: string; qty: number; price: number }[]; total: number }
) {
  const request = new SendEmailRequest({
    to: email,
    transactional_message_id: "5",
    message_data: {
      order_id: order.id,
      items: order.items,        // Accessible as {{ event.items }} in Liquid
      total: order.total,
      order_date: new Date().toISOString(),
    },
    identifiers: { id: userId },
  });

  return api.sendEmail(request);
}