Building Electron Apps That Scale: Lessons from Healthcare Software

After leading the development of Lucy, a healthcare software solution now serving over 100 doctors and clinics in Luxembourg, we've learned valuable lessons about building Electron applications that scale. Here's what we've discovered.

The Challenge of Desktop Apps at Scale

Desktop applications present unique challenges compared to web apps:

• Varied environments: Users run different OS versions, hardware configurations, and have different permissions.
• Offline capability: Medical software must work even when internet connectivity is unreliable.
• Data sensitivity: Healthcare data requires robust security at every level.
• Update management: Rolling out updates to hundreds of installations requires careful orchestration.

Architecture Decisions That Matter

1. Process Separation

Electron apps run in multiple processes. Smart separation is crucial:

// Main process: Handle system-level operations
// - File system access
// - Native OS integrations
// - Auto-update management

// Renderer process: Handle UI
// - React/Vue components
// - User interactions
// - API communications

Keep heavy computations off the main thread to maintain UI responsiveness.

2. Data Persistence Strategy

For Lucy, we implemented a hybrid approach:

• Local SQLite database for offline-first operation
• Sync engine for cloud backup and multi-device access
• Conflict resolution system for concurrent edits

This ensures doctors can access patient records even without internet, while maintaining data consistency across devices.

3. Security Layers

Healthcare data demands multiple security layers:

• Encryption at rest: All local data encrypted with AES-256
• Secure IPC: Validated communication between processes
• Context isolation: Renderer processes sandboxed from Node.js
• Audit logging: Every data access logged for compliance

Performance Optimization

Lazy Loading

Load features only when needed:

// Instead of importing everything upfront
const PatientModule = lazy(() => import('./modules/patient'));
const BillingModule = lazy(() => import('./modules/billing'));

This reduced our initial load time by 60%.

Memory Management

Electron apps can be memory-hungry. We implemented:

• Window pooling: Reuse window instances instead of creating new ones
• Image optimization: Compress and cache medical images intelligently
• Garbage collection triggers: Manual GC during idle periods

Native Module Optimization

For CPU-intensive operations like report generation, we use native modules:

// Native module for PDF generation
const pdfGenerator = require('./native/pdf-generator.node');

This provided 10x speedup compared to JavaScript-only solutions.

Update Strategy

Deploying updates to 100+ medical installations requires care:

Staged Rollouts

1. Internal testing
2. Beta group (5% of users)
3. Gradual rollout (25% → 50% → 100%)
4. Monitor for issues at each stage

Rollback Capability

Every update includes automatic rollback if critical errors are detected:

autoUpdater.on('update-downloaded', (info) => {
  // Store current version for potential rollback
  storeCurrentVersion();
  // Schedule update for next restart
  scheduleUpdate(info);
});

Lessons Learned

1. Invest in telemetry early: You can't fix what you can't measure
2. Design for offline first: Connectivity is never guaranteed
3. Test on real hardware: Emulators don't catch everything
4. Plan for scale from day one: Architecture changes are expensive later
5. Automate everything: Manual deployments don't scale

Conclusion

Building Electron apps that serve critical healthcare needs requires careful architecture decisions upfront. The investment in proper foundation pays dividends as your user base grows.

Interested in building a desktop application for your business? Contact us to discuss your requirements.