Senior Frontend Developer | NL

Impact the Future of Road Safety

Do you want to make the world a safer place? At Sensys Gatso
, we are driven by a singular passion: transforming traffic behavior to save lives. As a global leader in our field, we don’t just provide technology—we design the future of road safety.

We are looking for a high-caliber Senior Frontend Developer to join our international team in Haarlem and take a leading role in our React-based operator interface. This is a mission-critical position for a developer who thrives on ownership. You will join an established team today and grow into the in-house center of gravity for the frontend work. If you want real ownership of a mature, safety-critical product — not a greenfield toy — this is it.

As our Senior Frontend expert, you will serve as the sole frontend authority in our Haarlem office. While based locally, your impact extends globally: you will lead and collaborate closely with our contractor teams in eastern Europe to ensure seamless execution. You sit at the heart of the Engineering Department, acting as the vital link between our sophisticated hardware technology and our global clientele.

Your mission is to translate ambitious traffic safety goals into precision-engineered interfaces that are correct, robust and genuinely usable — with a real feel for interaction design, not just implementation. As the frontend specialist in a largely backend-driven environment, you will also be the person who carries the UI and UX perspective into engineering decisions and helps grow our in-house frontend capability.

If you are motivated by high-stakes challenges and empowered autonomy, you’ll find your home here.

The Professional Foundation:

• Engineering Expertise: 5+ years of experience developing complex interfaces for controlling real-time, device-facing and high-precision equipment. You are comfortable working both as a solo lead and as a collaborator.
• Interaction & UX design: A genuine affinity for interaction design and the user experience of an interface. You care how it feels to use, not only whether it renders.
• Technical Mastery:
  You are an expert in React, Type Script, gRPC, Git Lab, and Docker. Your toolkit includes deep experience with Redux, ESLint, Jest, and Cucumber-style testing.
• Architectural Mindset: A strong technical background that allows you to rapidly build user-friendly interfaces while maintaining a clean, scalable codebase.
• Communication:
  Fluent in English with the ability to synthesize complex technical data into clear documentation.

The Mindset & Spirit
:

• Adaptive Ownership:
  You thrive in a fluid environment. You are proactive, structured, and patient, capable of managing multiple international client requirements simultaneously.
• Customer-Centric Innovation:
  You act as a front-line advocate, energized by creating tangible value and representing our mission with pride.
• Technical Curiosity:
  You have a natural drive to explore latest technologies and an ability to expose backend features in an efficient, intuitive way.

The "Extra Mile" (Bonus Points):

• Native or near-native Dutch proficiency.
• Experience in traffic safety, type approvals, or technical certifications.

• UI Lead & Ownership: Take full end-to-end ownership of the user interface throughout the entire product lifecycle.
• Navigate Complexity: Translate intricate customer needs and hardware capabilities into technically sound, user-friendly solutions.
• Maintain & Evolve: Drive structural improvements to our current technical solutions, ensuring the frontend is future-proof.
• Cross-Functional Synergy: Act as the bridge between customers, stakeholders, and local/remote backend developers to ensure seamless integration.
• Radical Simplification: Distill complex technical concepts into intuitive designs, inspiring peers to pursue simplicity in every solution.

• Competitive Compensation: A high-end salary plus a performance-based bonus structure.
• Work-Life Balance: 31.5 days of annual leave (25 days plus 6.5 ATV days) to keep you refreshed.
• Empowered Autonomy: A high-trust environment where you are empowered to take the lead and drive innovation.
• Continuous Learning: Dedi…