How Worldline Boosted MiniCashier App Performance on SmartPOS with the Kotzilla Platform

About the project

Worldline’s MiniCashier app is a Kotlin Multiplatform application deployed on Android SmartPOS terminals. These secure, all-in-one payment devices are used by merchants across Europe.

The app plays a central role in delivering fast and reliable access to payment services, where performance is critical for both users and support teams.

Challenge

As the team expanded the app’s feature set and modernized its architecture, they began refactoring key components to improve maintainability and responsiveness.

However, to ensure these improvements delivered real-world performance benefits and to catch regressions early, they needed deeper visibility into startup behavior and runtime performance, especially in production.

Solution

By integrating the Kotzilla Platform, the Worldline team was able to:

✅ Gain deep visibility into startup and runtime performance
✅ Trace app startup and identify slow or blocking component resolutions
✅ Profile thread execution in both debug and production builds to pinpoint bottlenecks
✅ Compare debug and release builds with full contextual data

Results

🔥Validated how the refactored architecture and code improved app startup time early to ensure performance goals were met.
🔥 Achieved clear visibility into performance differences between debug and production environments
🔥 Continuous monitoring enabled safer, faster feature iteration.
🔥 Early issue detection helped prevent downtime, reduce support efforts, and enhance the merchant experience.

Refactor with confidence by monitoring startup time, detecting issues early, and continuing to ship fast.