Senior Frontend Engineer (React)

As a Senior Frontend Engineer (React) at November Five, you will play a key role in designing, developing, and maintaining high-quality web applications used by thousands of users. You will take technical ownership of projects, mentor other engineers, and collaborate closely with product managers, designers, and backend engineers to deliver robust, scalable, and memorable digital experiences. You will help shape our engineering culture, drive architectural decisions, and ensure our products meet the highest standards of performance, accessibility, and usability.

IF YOU JOIN US, YOU WILL:

• Take technical ownership of frontend projects, setting standards for code quality, architecture, and best practices.
• Design, build, and maintain advanced single-page applications using React, TypeScript, and modern frontend technologies.
• Lead technical discussions, code reviews, and architectural decisions for web products.
• Collaborate with product managers, designers, and backend teams to define, design, and ship impactful new features.
• Drive the adoption of best practices in testing, automation, and continuous integration/deployment (CI/CD).
• Ensure the best possible performance, accessibility, and user experience across browsers and devices.
• Integrate seamlessly with backend APIs and headless CMS platforms such as DatoCMS, optimizing for reliability, scalability, and content workflow.
• Stay up-to-date with the latest trends, libraries, and technologies in frontend development, proactively introducing improvements to our stack.
• Mentor and support junior engineers, sharing knowledge and promoting best practices.
• Foster a culture of ownership, innovation, and continuous improvement within the team.

• 4+ years of professional experience developing and maintaining high-quality web applications, with a strong focus on React and the modern JavaScript/TypeScript ecosystem.
• Deep technical expertise in React, ES6+, and related libraries and frameworks (e.g., Redux, Apollo, GraphQL, Next.js).
• Demonstrated experience leading technical projects, making architectural decisions, and mentoring other engineers.
• Strong understanding of frontend architecture, component design, state management, and performance optimization (e.g., RAIL, PRPL).
• Experience building and maintaining build pipelines using Webpack, Vite, or similar, and working with CI/CD tooling.
• Hands-on experience integrating and working with modern headless CMS platforms (such as DatoCMS, Contentful, Sanity, or similar), including schema design, API integration, and optimizing content workflows.
• Familiarity with progressive enhancement, accessibility (WCAG), and web standards.
• Experience with service workers, PWA development, and modern frontend innovations (e.g., WebAssembly).
• Experience integrating with backend APIs and working in multidisciplinary, agile teams.
• Excellent problem-solving, debugging, and communication skills.
• Passion for learning, sharing knowledge, and mentoring others.
• Experience with React Native is a strong plus.
• Bachelor's degree in Computer Science, Engineering, or equivalent practical experience.
• Fluency in English; Dutch is a plus.

Why November Five?

• Because the work matters. And so do our people.
• Ship real products for brands like Coca-Cola, Le Pain Quotidien & Telenet.
• Work in a high-standard, fast-paced, no-BS team.
• Launch work that actually lands - no endless cycles, just real impact.
• Enjoy full trust, a fully optimized benefits package with options for a mobility budget or company car, smartphone budget, mobile subscription, MacBook, pension plan, hospitalization insurance, net expenses, meal vouchers, 12 additional holidays & shared rewards
• Work from a stunning Antwerp HQ

We're November Five. We're makers. Doers, designers, strategists. Different backgrounds, one mindset. We say what we mean and do what we say. Passion walks in the door; expertise evolves over time. Feedback is direct. We're hard on the work but soft on the people behind it. As craftsmen and women across our core capabilities, our passion transcends our expertise, and the roles we assume are fluid. United in our drive to defy limits and move beyond, we collaborate deeply, always on the lookout for more allies.