email

// With a lead form submission
window._upstack('track', 'lead', {
  email: 'customer@example.com',
  value: 0,
  currency: 'USD'
});

// With a purchase
window._upstack('track', 'purchase', {
  email: 'customer@example.com',
  transactionId: 'ORD-123',
  value: 99.99,
  currency: 'USD'
});