I build fast, scalable, human-friendly web apps.
Senior developer specialised in React, Next.js and modern frontend architecture.
I help teams turn complex ideas into maintainable, high-performance products.
Why work with me?
Experienced programmer — years of experience with production-grade applications
Strong in architecture — scalable, testable and future-proof
UX & performance first — fast loading times, fast interactivity
Clear communication — no buzzwords, just clear choices
Independent and a team player — plug-and-play in existing teams
I don't just think in code, but in solutions.
Specialisations
React (hooks, context, performance tuning)
Next.js (App Router, SSR, ISR, SEO)
TypeScript (strict, predictable, secure)
Design systems & component libraries
CMS solutions & page builders
Animations with Framer Motion
Web performance & SEO
Testing with Jest, Playwright and Cypress
Automation and CI
In my work, I have dealt with many other languages and tools. Can't find what you need? Feel free to contact me to see if I can help you anyway.
Who I work for
Start-ups that want to build quickly but thoroughly
Companies with an existing React/Next.js platform
Agencies that require a senior front-end developer
Entrepreneurs seeking a technically strong partner
Whether it's a new project, further development or rescuing an existing codebase — I'm happy to step in.
About me
I am Sjoerd van den Berg, a programmer with a penchant for clean code, smart abstractions, and products that feel good for both users and developers.
I enjoy working on projects where quality matters and technical choices make a difference. No over-engineering, no shortcuts that will cost you dearly later on.
I am originally from the Netherlands, but in 2022 I decided to move with my family to sunny Spain. I have now been living in Spain for a few years and am successfully working from home for international clients.
Curious about my work experience?
You can find more details about my work experience on LinkedIn: linkedin.com/in/sjoerdberg
Languages
This website is available in multiple languages. Transparency is important to me, so here's how it works:
🇬🇧 English — fluent
🇳🇱 Dutch — native language
🇪🇸 Spanish — learning / basic
🇩🇪 German — good understanding, limited speaking
🇫🇷 French — not spoken
🇮🇹 Italian — not spoken
For projects and communication, I work professionally in English and Dutch.
This is how I can assist you
New React or Next.js application
Performance and SEO optimisation
Setting up or improving front-end architecture
Further development of existing projects
Debating technical choices
Not sure if I'm the right person for the job? Feel free to send me a message — I'd be happy to help you figure it out.