Zero-Cost Tracking

Conversion tracking for lead gen sites using @leadgen/conversion-tracking package.

When To Use

• Lead gen site with Google Ads + GA4 + Meta tracking
• Calculator, contact form, or callback conversions
• Need Enhanced Conversions for Safari/iOS
• Need first + last touch UTM attribution
• Consent-aware tracking (GDPR compliant)

Does NOT Handle

• Cross-domain tracking
• Ecommerce / product tracking
• A/B test tracking
• Real-time dashboards

Architecture

Cloudflare Edge:
├── Google Tag Gateway (proxies GTM, bypasses ad blockers)
└── Zaraz (Meta CAPI server-side)

Browser:
├── dataLayer.push() → GTM → GA4 + Google Ads
├── zaraz.track() → Meta CAPI
└── fetch('/api/lead') → Sheets

Installation

npm install @leadgen/conversion-tracking

Setup

1. Add to astro.config.mjs

import { defineConfig } from 'astro/config';
import tracking from '@leadgen/conversion-tracking';

export default defineConfig({
  integrations: [
    tracking({
      gtmId: 'GTM-XXXXXXX',     // Required
      currency: 'GBP',          // Optional (default: GBP)
      sessionTimeoutMinutes: 30, // Optional (default: 30)
      debug: false,             // Optional
    })
  ]
});

This auto-injects GTM and initializes tracking on every page.

2. Track Form Conversions

import { trackConversion, buildSheetsPayload } from '@leadgen/conversion-tracking/client';

async function handleSubmit(e: SubmitEvent) {
  const form = e.target as HTMLFormElement;

  // 1. Validate FIRST
  if (!form.reportValidity()) return;

  // 2. Prevent default
  e.preventDefault();

  const formData = new FormData(form);
  const email = formData.get('email') as string;
  const phone = formData.get('phone') as string;

  // 3. Track conversion (GTM + Zaraz)
  const result = trackConversion('quote_request', {
    email,
    phone,
    value: calculatedQuote,
    currency: 'GBP',
  });

  // 4. Send to Sheets (use crm-integrations skill)
  const payload = buildSheetsPayload({
    eventType: 'quote_request',
    name: formData.get('name') as string,
    email,
    phone,
    value: calculatedQuote,
  });

  await fetch('/api/lead', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(payload),
  });

  // 5. Redirect
  window.location.href = '/thank-you';
}

3. Phone Links

---
import PhoneLink from '@leadgen/conversion-tracking/components/PhoneLink.astro';
---

<!-- Header/footer - no value -->
<PhoneLink phone="+447123456789">Call us</PhoneLink>

<!-- Calculator page - with quote value -->
<PhoneLink phone="+447123456789" value={calculatedQuote} currency="GBP">
  Call for this quote
</PhoneLink>

4. Calculator Events

import {
  pushCalculatorStart,
  pushCalculatorStep,
  pushCalculatorOption
} from '@leadgen/conversion-tracking/client';

// When calculator loads
pushCalculatorStart();

// When user advances to step
pushCalculatorStep(2);

// When user selects option
pushCalculatorOption('bedrooms', '3');

5. Form Abandonment

import { pushFormAbandon } from '@leadgen/conversion-tracking/client';

let lastField = '';
let formStarted = false;
let abandonTimeout: number;

form.addEventListener('focusin', (e) => {
  const field = (e.target as HTMLElement).getAttribute('name');
  if (field) {
    lastField = field;
    if (!formStarted) {
      formStarted = true;
      abandonTimeout = window.setTimeout(() => {
        pushFormAbandon('quote', lastField);
      }, 60000);
    }
  }
});

form.addEventListener('submit', () => clearTimeout(abandonTimeout));

Events Matrix

DataLayer Events

Conversion Events (with attribution)

dataLayer.push({
  event: 'quote_request',
  lead_id: 'LD-2025-01-15-abc',
  tracking_version: 'v2.0',
  session_id: 'sess_abc123',
  page_url: '/calculator',
  device: 'mobile',
  user_email: 'test@example.com',
  user_phone: '+447123456789',
  value: 450,
  currency: 'GBP',
  // First touch
  first_utm_source: 'google',
  first_utm_medium: 'cpc',
  first_utm_campaign: 'removal-bristol',
  first_gclid: 'CjwKCAiA...',
  // Last touch
  last_utm_source: 'google',
  last_utm_medium: 'cpc',
  last_gclid: 'CjwKCAiA...',
});

Calculator Events (minimal)

dataLayer.push({
  event: 'calculator_step',
  step: 2,
  tracking_version: 'v2.0',
  session_id: 'sess_abc123',
});

Sheets Payload

buildSheetsPayload() returns:

GTM Setup

Create these in GTM:

Variables (Data Layer)

• DLV - value, currency, lead_id, session_id
• DLV - user_email, user_phone, device, page_url
• DLV - first_utm_source, first_utm_medium, first_gclid
• DLV - last_utm_source, last_utm_medium, last_gclid
• User Provided Data (email + phone for Enhanced Conversions)

Triggers (Custom Event)

• phone_click, quote_request, callback_request, contact_form
• calculator_start, calculator_step, calculator_option, form_abandon

Tags

• CookieYes CMP (Consent Init)
• Conversion Linker (Initialization, requires ad_storage)
• Google Tag (All Pages, requires analytics_storage)
• GA4 Event tags for each event
• Google Ads Conversion tags with Enhanced Conversions

GTM variables should have "Data Layer Variable" type with auto-event variable name matching the event property.

Cloudflare Setup

Google Tag Gateway

Cloudflare → [domain] → Speed → Optimization → Google Tag Gateway → Enable

Zaraz (Meta CAPI)

Cloudflare → [domain] → Zaraz → Tools → Facebook Pixel

Settings:
- Pixel ID: [from Meta]
- Access Token: [from Meta] ← ONLY HERE, never in code!
- Server-side: Enabled

Triggers:
- phone_click → Lead
- quote_request → Lead
- callback_request → Lead
- contact_form → Lead

For Zaraz trigger setup, match each event name to track a corresponding Meta Lead event.

Key Behaviors

• Session: localStorage + 30min inactivity timeout, same across tabs
• Phone dedupe: Once per session, page reload allows new fire
• Attribution: First touch never overwritten, last touch always updated
• View Transitions: Auto re-captures params on navigation

Core Rules

1. GTM is authority — consent.ts is read-only helper
2. localStorage safety — Package handles try/catch for Safari
3. Form order — reportValidity() → preventDefault() → track → redirect
4. Attribution on conversions only — calculator events minimal
5. Meta token in Zaraz only — NEVER in code or env vars

Related Skills

• crm-integrations — For Sheets webhook + retry queue
• astro-forms — For form validation patterns

Forbidden

• Meta Access Token in code
• Blocking form on tracking failure
• Attribution data on calculator events
• Overriding GTM consent from JavaScript