Kali

The core technical challenge was making Shopify do something it was never designed to do. Kali's marketplace runs on Shopify, but Shopify has no native concept of step-based rewards, earned point balances, or per-user dynamic discount tiers. We had to build a custom middleware engine that sat between the mobile app and Shopify: reading step counts from Apple HealthKit, converting them to Kali points in real time, generating unique discount codes via the Shopify Admin API, enforcing per-user redemption limits, and writing all step and reward history to our own database — all without disrupting the native Shopify checkout experience users already trusted. On top of that, tracking and modifying user data across two systems (our backend and Shopify's customer records) without creating sync drift was a constant engineering constraint.

We rebuilt the Kali website from scratch — clean editorial typography, smooth scroll animations, and a wellness-brand aesthetic that matched the premium feel of the marketplace. For the mobile app, we built in React Native for fast iOS deployment. Daily step data is pulled via the HealthKit API and synced to our Node.js backend, where a custom reward engine calculates Kali points and eligibility for each user. When a user redeems points, we generate a single-use Shopify discount code via the Admin API, tied to that user's account and expiry window. The Shopify Storefront API powers the in-app marketplace — users browse curated wellness brands and apply earned discounts without leaving the app. Firebase Cloud Messaging handles push notifications for step-goal reminders and new brand announcements.