Overview
As Full Stack Developer on a team of 3, I rebuilt a critical desktop application for a retail chain managing hundreds of stores. The legacy Electron-based POS client suffered from slow synchronization and high memory usage, directly impacting store operations and causing inventory discrepancies.
The Challenge
Legacy sync system taking 5+ minutes, causing operational delays for retail stores processing half a million daily transactions.
- Legacy Electron app consumed 800MB+ RAM, causing crashes on older hardware
- Full data sync took 5+ minutes, blocking store opening procedures
- Inventory discrepancies between local and server data reached 15%
- No offline capability meant network issues halted all operations
Technical Approach
- Rebuilt using Tauri with Rust backend for an ~80% smaller binary and better performance
- Implemented delta sync algorithm - only changed records transfer
- Created local SQLite cache with conflict resolution for offline-first operation
- Built background sync service that runs without blocking UI operations
Key Decisions
Tauri over Electron
80% smaller binary size and native Rust performance for data processing
SQLite for local storage
Battle-tested embedded database with excellent concurrent read performance
Operational Transform for conflicts
Predictable conflict resolution that preserves user intent
Results
- Sync time reduced from 5+ minutes to under 10 seconds (97% improvement)
- Memory usage dropped from 800MB to under 100MB
- Inventory discrepancies reduced from 15% to under 5%
- Stores can now operate fully offline for up to 24 hours
Lessons Learned
- Native code (Rust) makes a massive difference for data-intensive operations
- Delta sync requires careful versioning - timestamp-based approaches have edge cases
- Retail environments have unreliable networks - offline-first is not optional