Senior Frontend Developer | Haarlem, NL

Sensys Gatso Group; Haarlem; On-site; EUR 70,000 - 110,000; Full time

Benefits offered by this job

Competitive compensation

Work-life balance (31.5 days)

Autonomy to lead

Continuous learning budget

Inclusive global culture

Team events

Job summary

Sensys Gatso Group in Haarlem seeks a Senior Frontend Developer to own the UI of our React-based operator interface and lead frontend decisions. You will collaborate with contractor teams in Eastern Europe and bridge hardware knowledge with client needs.

You will shape UX, maintain a scalable codebase, and grow our in-house frontend capability within a mature, safety‑critical product.

Qualifications

• 5+ years of experience developing complex interfaces for real-time, device-facing systems.
• Strong focus on user experience and interaction design for frontend interfaces.
• Proficient in React, TypeScript, gRPC, GitLab, and Docker; deep experience with Redux, ESLint, Jest, and Cucumber-style testing.
• Architectural mindset for scalable, clean frontend codebases.
• Fluent in English; able to translate technical data into clear docs.

Responsibilities

• Take full end-to-end ownership of the user interface throughout the product lifecycle.
• Translate customer needs and hardware capabilities into technically sound, user-friendly solutions.
• Drive improvements to ensure frontend remains future-proof.
• Act as bridge between customers, stakeholders, and backend developers for seamless integration.
• Distill complex concepts into intuitive designs and promote simplicity.

Skills

React

TypeScript

gRPC

GitLab

Docker

Redux

ESLint

Jest

Cucumber testing

UI design

Tools

Docker

GitLab

Job description

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.

The Role

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 Mindset & Spirit

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, TypeScript, gRPC, GitLab, 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.

Your Mission

• 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.

What We Offer

• 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: Dedicated budget and structured personal development plans to keep you at the forefront of the industry.
• Inclusive & Global Culture: A vibrant, international workplace where diversity is celebrated and collaboration is key.
• Team Connection: Regular social events and team-building activities to foster a genuine sense of community.

About Sensys Gatso Group

Defining the Standard in Traffic Safety Sensys Gatso Group is the global leader in traffic enforcement and safety solutions. Born from the strategic merger of Sensys Traffic AB and Gatso Beheer B.V., we combine decades of heritage with cutting-edge innovation. With subsidiaries spanning Australia, Germany, the Netherlands, Sweden, and the USA, and a strategic presence in the UAE, we operate on a truly global scale.

Our Mission We partner with central and local governments to solve the complex challenges of modern mobility. In an era of increasing urbanization, Sensys Gatso provides the "smart city" infrastructure required to manage highways, secure rural roads, and enhance the quality of life in urban centers.

Innovation & Stability Publicly traded on the NASDAQ OMX Stockholm, we offer the stability of a market leader with the agility of a tech innovator. Join a team of 200+ dedicated professionals who are committed to making the world’s roads safer, one solution at a time.