Improving Maintainability of a Diagnostic Code Application System
KoolCode is a mobile app used by field technicians to look up parameter and alarm codes for electronic controllers in refrigeration and HVAC installations. My bachelor project at Danfoss redesigned the system to improve maintainability while preserving existing workflows.
Overview
The original system had two pain points:
- two independent native codebases (Android and iOS) that diverged over time
- manual transcription of PDF user guides to populate the diagnostic code dataset
The redesigned system addresses both:
- a single cross-platform app built with React Native and Expo, using an MVVM architecture with a custom observable state layer
- an offline-first data flow combining a bundled seed dataset, chunked local persistence, and timestamp-based delta sync for reliable field operation
- a restructured admin panel with assisted extraction tooling that helps maintainers convert structured fragments from controller PDFs into the backend schema
Result
The project replaced two divergent native codebases with a single shared implementation and automated a previously manual extraction workflow. It also supports the argument that cross-platform development is a viable trade-off for read-heavy, lookup-oriented use cases like KoolCode.