Frontend Developer

OneSource Consulting; Den Haag; Remote; EUR 50,000 - 70,000; Full time

Job summary

A consultancy firm in the Netherlands is seeking a Frontend Developer to aid in the redevelopment of a government data platform. The successful candidate will focus on creating an accessible and maintainable frontend using React, with responsibilities including optimizing user interfaces and ensuring integration with backend systems. Applicants should have over 3 years of frontend experience, familiarity with WCAG standards, and experience working with REST APIs. This is a contract position aimed at mid-senior level professionals.

Qualifications

• 3+ years of frontend development experience.
• 2+ years experience with React.

Responsibilities

• Translate user research insights into an accessible redesign.
• Implement new UI following NL Design System principles and WCAG standards.
• Optimize frontend and ensure integration with backend systems.
• Deliver maintainable and well-documented code.
• Contribute to data.overheid.nl, ensuring a reliable user experience.

Skills

WCAG / DigiToegankelijk accessibility standards

REST APIs

web security guidelines

React

Next.js

design systems

component libraries

CI/CD (Git)

Drupal

UX knowledge

SonarQube

Cypress

Job description

Talent Acquisition Consultant | IT Recruiter | Netherlands

KOOP is seeking a Frontend Developer to contribute to the ongoing development of data.overheid.nl—the national platform that makes Dutch government data discoverable and reusable.

You will play a key role in the accessible redesign of the platform and help implement a future‑proof, consistent, and reusable frontend built on React.

Key Responsibilities

• Translate user research insights into an accessible redesign.
• Implement the new UI following NL Design System principles and WCAG accessibility standards.
• Optimize the frontend and ensure seamless integration with backend systems.
• Deliver high‑quality, maintainable, and well‑documented code.
• Participate in the continuous development of data.overheid.nl, ensuring a reliable user experience for searching and reusing government datasets.

Requirements

Technical Skills

• Experience with WCAG / DigiToegankelijk accessibility standards
• Experience integrating with REST APIs
• Knowledge of web security guidelines

Experience

• 3+ years frontend development
• 2+ years React experience

Preferred Skills

• Experience with Next.js
• Working with design systems / component libraries
• CI/CD (Git)
• Drupal experience
• UX knowledge
• SonarQube familiarity
• Cypress for testing
• SAFe Agile certification (or willingness to obtain)

Seniority Level

Mid‑Senior level

Employment Type

Contract

Job Function

Information Technology