Sefrijn

Senior Software Engineer | Product-Focused Development | Web & Mobile

I'm a Full-Stack Software Developer with 14 years of experience building digital products and helping teams turn complex ideas into practical solutions. My background spans software development, design, entrepreneurship, and education, giving me a broad perspective on how products are conceived, built, and grown. My technical expertise is centered around React, React Native, TypeScript, and modern frontend architecture, with backend and API development across various languages and frameworks (Kotlin, .NET, Laravel).

I enjoy working at the intersection of technology, product, and people: taking ownership of products, mentoring developers, shaping architecture, and helping teams balance user needs, business goals, and long-term maintainability. Years of working with NGOs, government organisations, established brands, and startup teams have taught me how to quickly understand different contexts, align diverse stakeholders, and build solutions that matter to the people who use them.

Projects include building the mobile app for the Hipsy event platform , setting up a Design System for the City of Eindhoven, developing signage software for Van der Valk Hotels, contributing to the Debat Gemist app for the Dutch Parliament, and helping create a global volunteer platform for Greenpeace International. I’m particularly drawn to projects that combine technical excellence with positive social, cultural, or environmental impact.

Outside of software, you can find me playing as an Ecstatic Dance DJ across the Netherlands and Europe. Music and movement have always been vital in my life, providing a creative outlet and balancing out screentime.