Shipped applications, production platforms, and enterprise integrations.
These represent work shipped to real users or deployed in production environments — with engineering complexity, ownership, and real-world constraints.
AndroidProduction
Hymnario Android App
Production Android app with ~5,000 users — full product ownership including Play Store publishing, subscription monetization, and multi-year maintenance
Built around a custom MIDI rehearsal engine with guided accompaniment, real-time chord transposition, and offline-first Firebase architecture. OCR-extracted hymn content, synchronized lyric rendering, and multi-channel audio playback shaped the product experience over 6+ years of ownership.
Integration engineer — hardware-software bridge connecting biometric devices to payroll systems
Built enterprise integration connecting ZKTeco biometric attendance hardware with payroll workflows. Architected resilient sync for unreliable device networks and distributed enterprise environments.
Outcome / Impact
Built custom API ingesting attendance records from biometric hardware devices
Engineered resilience workflows for unreliable device connectivity and data recovery
Technical stack
.NET REST APIs SQL Server Hardware Integration
AndroidProduction
Futoshiki Puzzle App
Constraint-based puzzle app with explainable solving logic, custom Canvas rendering, and full Play Store ownership
Constraint-based puzzle system with explainable solving logic and 24,000+ curated puzzles. Custom Canvas rendering engine with deterministic validation, immutable state architecture, and Firebase backend. Play Store ownership with Play Billing + AdMob monetization. Modernized with Navigation Component, Crashlytics, and AC-3 constraint engine.
Migrated unstable legacy Excel add-in to Google Sheets add-on for enterprise payroll workflows. Full-stack delivery with React frontend, Apps Script runtime adaptation, OAuth2 authentication, and WebSocket synchronization within platform constraints.
Outcome / Impact
Evaluated and led the migration of a legacy Excel add-in to a Google Sheets add-on using React and Apps Script
Built OAuth2 authentication flows and adapted WebSocket synchronization to work inside the Apps Script environment
Technical stack
React TypeScript Google Apps Script OAuth2 WebSockets Material Design clasp Google Cloud
Architecture concepts & in progress
Systems being designed, iterated, and explored.
Architecture-first projects currently in development — focused on domain modeling, local persistence, and building the right foundation before shipping.
AndroidIn Development
Repertoire App
Workflow-focused Android app for music teams — complex domain modeling, personalized singer keys, and local-first sync architecture
Workflow app for music teams handling song libraries, singer assignments, and rehearsal preparation with personalized key transposition. Built with multi-database architecture for data isolation, local-first reliability, and complex domain modeling.
Private repository — architecture details available upon request.
Technical stack
Kotlin Room DB MVVM StateFlow Firebase Auth Firestore
Financial Systems Concept
AndroidConcept
FlowControl
Financial systems architecture exploration — payment scheduling, debt modeling, and future simulation systems
Architecture-first exploration of personal finance tracking systems. Demonstrating domain-driven design for payment schedules, debt modeling, recurring transaction logic, and future payment forecasting with maintainable Android architecture.
Outcome / Impact
Payment scheduling and debt modeling for recurring financial transactions
Future payment forecasting and simulation systems architecture
Domain-driven design for maintainable financial domain logic
Technical stack
Kotlin Room DB Jetpack Compose Coroutines
Contact
Looking for someone who ships production software?
I build and ship reliable software across Android apps, production Nuxt/Vue frontend systems, and backend APIs. Focused on maintainable architecture, execution, and getting features to users.
