Senior iOS Developer at E note GmbH – Intelligent Sheet Music

Built an intelligent sheet-music viewer and a notation engine for PDF, and a proprietary digital format across iOS/iPadOS and macOS (Catalyst). Delivered offline-first experience with local caching, background syncing, online sync, plus a behavior-based download prioritization for assets. Led a major architecture overhaul, improving UI smoothness, performance, and reliability by introducing async/await, actors, and Combine, increasing team productivity by ~50% and raising test discipline and bug reporting quality (up to 2×). Implemented product analytics (Amplitude) to track feature usage and support data-driven product decisions. Delivered a note-editing feature with complex editing/gestural UI that contributed to a €20M investment from the European Innovation Council and Dieter von Holzbrinck Ventures.

Contributed across iOS development, owning end-to-end from requirements analysis through implementation and testing. Mentored and supported 2 junior iOS engineers, improving their delivery efficiency by ~250% within one year. Maintained iOS CI/CD, delivered 10+ mobile apps across native iOS with Objective-C, Swift, Android, and Ionic, supporting reliable beta and production releases.

Senior Full-stack Developer at Appsun – Software Development Agency

Built and shipped client apps end-to-end using PHP (Laravel) and Python (Django/Tornado), RabbitMQ, and PostgreSQL, TypeScript, covering backend, frontend, and production support. Developed REST APIs, database features, and server-side logic.