Senior Android & KMP Engineer for complex mobile products
I help teams ship fintech, realtime, and high-scale mobile apps — from architecture and migrations to release quality.
🇳🇱 Dutch fluent · English · Polish · EU timezone
Book a callFollowing a multi-country acquisition, the banking app needed a full rebranding and migration across 4 markets — with no tolerance for regressions in production. I joined the core team to drive the Android rebranding effort: 30+ XML-to-Compose migrations, WCAG accessibility rollout, monorepo Gradle alignment, and introduced ADRs to improve architectural decisions. Caught and resolved 40+ UI regressions before they reached users.
Wire needed a full rewrite of its Android app to modern standards while keeping millions of users unaffected. I built the app from scratch using Jetpack Compose and designed the shared KMP business logic layer — covering networking (gRPC), data persistence (SQLDelight), and domain models shared with iOS. The migration completed with zero downtime, and KMP became the architectural foundation across both platforms.
Needed a fully working fitness app shipped to Google Play on a tight timeline with a single-person team. As sole developer, I handled architecture, UI, and release management end-to-end — delivering a complete Flutter fitness product from concept to production in 4 months.
Banking apps, encrypted messengers, trading platforms. I’ve shipped them all — here’s where I add the most value.
Bring structure to complex Android codebases. Clean module boundaries, MVI, Kotlin Coroutines, and testable code that teams can confidently maintain and extend at scale.
Replace duplicated platform code with a single shared business logic layer. Networking, persistence, and domain models that work reliably on both Android and iOS — proven at Wire Messenger.
Migrate View-based UIs to Jetpack Compose incrementally, without breaking existing features. Delivered 30+ XML-to-Compose migrations at Santander across a multi-country monorepo.
Raise the quality bar before shipping: snapshot testing, WCAG accessibility, CI/CD pipelines, performance profiling, and release management. Fewer regressions in production, more confidence in every release.
No surprises, no scope creep. Here’s exactly what working together looks like — from first call to shipped product.
30 minutes to understand your problem, goals, and constraints. We align on scope before a single line of code is written.
I write down what we’re building, how, and when — just enough to move with confidence. No 40-page documents, just a clear plan we both agree on before anything starts.
You get a weekly update and something you can actually test. Real progress, not slide decks. Modern tooling keeps delivery fast without cutting corners on quality.
CI/CD set up, docs written, and I walk your team through what was built. You own it from day one — not just the files, but the understanding of why things are the way they are.
Optional retainer or bug-fix period. I stay reachable after delivery — not just until the invoice clears.
7 years building real things. Banking apps across 4 countries, an encrypted messenger for millions, a BLE mesh SDK from scratch — the stack reflects the work.
Android
Platform & Connectivity
Tooling & Quality
Languages
Dev Tooling
Available for remote EU roles and contracts. Building side projects, exploring KMP opportunities, and applying modern tooling (AI-assisted development, Cursor, LLM APIs) to sharpen delivery speed without compromising quality.
Hired into the core team delivering features across 4 countries; 30+ XML → Compose migrations, WCAG accessibility rollout, monorepo Gradle alignment, introduced ADRs. Acted as bridge between the Polish business unit and Santander Digital Services. Later led the Poland mono repo migration and the full rebranding to Erste following the acquisition.
Built Wire Messenger from scratch with Jetpack Compose — end-to-end architecture decisions, daily collaboration with designers on product direction, E2E-encrypted features over gRPC, and shared business logic via KMP (Ktor / Koin / SQLDelight).
Multi-client Android delivery: AlleFolders Dutch brochure-browsing app (bug fixes & features), BlockTrade crypto platform with live prices and real-time graphs (RxJava, reactive programming), multiple radio app releases, and FitCrony fitness app built solo in Flutter.
Built a BLE-mesh Android SDK as sole engineer — replicating the iOS implementation through unit tests with full documentation. The SDK powered a BLE mesh where dedicated devices exchanged data with phones acting as radars for BLE signals. Ran in parallel with a companion pet-tracking demo app.
Electrical & Electronics Engineering — foundation in embedded systems, signal processing, and hardware-software integration. Originally from Poland; studied and lived in the Netherlands for 14 years.
Looking to hire a Senior Android or KMP engineer for a remote EU role or contract? Let’s talk.
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