Wiebe Geertsma, BSc.

International mobile-first agency · 500–1,000 employees

• Implement new features into banking apps and update them to modern standards.
• Maintain the apps to keep them running smoothly.
• Alongside the client work, built hands-on expertise in AI orchestration — directing AI agents to migrate a banking app's legacy UI from XML/Fragments to Jetpack Compose.
• Configured agents across different effort levels and models, with a focus on token efficiency.
• Started out with GitHub Copilot, but now works almost exclusively — about 99% of the time — with Anthropic's Claude Code.

Independent project — hand-built after leaving Booqable, now growing it into a real product.

• Architected a cross-platform app from scratch — Kotlin Multiplatform and Compose Multiplatform for Android and iOS, sharing one domain layer, plus a Next.js web client.
• Built a single Ktor backend on DigitalOcean App Platform serving all three clients over one REST API.
• Shipped an AI-powered feature that estimates meal macros from a plain-language description, removing the biggest friction point in food logging.
• Kept core features — barcode scanning, food catalog, recipes, and shopping lists — free and ad-free by design.
• Handles payments via Stripe for an optional Supporter membership tier.

SnappCar — a peer-to-peer car-sharing platform based in Utrecht.

• Android development work during a short-term engagement.

Rental software company · 30–50 employees

• Architected a performant, reactive, and layered application using the Repository Pattern and Dependency Injection (Dagger/Hilt).
• Implemented a domain layer for shared business logic with the iOS app using Kotlin Multiplatform (KMP).
• Established CI/CD pipelines for automatic deployment to app testers and the Google Play Store.
• Built the UI layer with state holders, enhancing responsiveness and maintainability.
• Integrated push notifications with instant reply functionality to boost user engagement.
• Conducted Unit Testing and UI Testing to ensure app reliability and performance.
• Optimized the app using R8 for code shrinking and obfuscation.
• Managed a SQLite database for local data storage.
• Wrote complex SQL queries to improve the performance of data-heavy screens.
• Fetched data from a JSON:API spec API.

Construction cloud-software startup · from my 2015 internship to leading the mobile team, through the acquisition by Exact.

• Built the Android app from scratch during my 2015 internship — later published as 'Exact Construction'.
• Implemented offline functionality for use on construction sites without connectivity.
• Migrated the app from Java to Kotlin, introducing a Repository pattern and Dependency Injection (Dagger/Hilt).
• Converted the iOS app's Objective-C codebase to Swift — effectively rewriting the iOS app alongside the Android work.
• Designed a performant, reactive app, optimized for large and complex datasets.
• Managed the SQL database using Realm and fetched data from a JSON API.
• Integrated push notifications.
• Established CI/CD pipelines for automatic deployment to app testers and the Google Play Store.
• Managed app releases.
• Grew from intern to leading a mobile team of 6 as the app and company scaled.