Extensibility

Advanced setup patterns like multi-list routing and safe rollout guidance.

Extensibility is used when the default Klaviyo connector behavior does not match the Brand’s data model.

The most common extension is multi-list subscription routing.

Real-world examples

• A Brand routes consents_email to a “Newsletter” list and consents_sms to a “VIP SMS” list.
• A partner needs custom list routing based on store, language, or program.

Custom mapping

/**
 * Maps The Wallet crew account data to Klaviyo format.
 *
 * @param {Object} account - Data coming from The Wallet Crew
 * @param {Object} data - Data sent to Klaviyo. Standard mapping is already applied on this object.
 */
function mapToKlaviyo(account, data){
  const phoneNumber = account["phoneNumber"]
  if(phoneNumber){
    data.phone_number = phoneNumber; 
  }
}

export default function(context) {
  context.register('extensions.klaviyo.mapper', {
    MapToKlaviyo: mapToKlaviyo
  });
}

Multiple list subscriptions via /server/script/klaviyo.js

This pattern replaces the single listId configuration.

Implementation details and code example: Multiple lists (advanced).

Rollout and safety guidance

A conservative rollout reduces surprises in segmentation and consent.

• Start in staging.
• Validate on a small set of test profiles.
• Monitor events and profile properties in Klaviyo.
• Roll back by removing the script entry point, then re-test.

FAQ

Does a script change affect existing profiles?

Yes. Once deployed, scripts can change how subscription updates are computed for any profile that goes through an enrolment flow.

Validation in staging is recommended.