Frontend Developer
Summary
Frontend engineer in Belfast joining a brand-new UI team at a $3.8B cloud security unicorn building an eBPF-powered, real-time threat detection platform. Day-to-day: designing React/TypeScript components through production, shaping API design with backend teams, and driving UI quality, on a hybrid 3-days-in-office model.
Frontend Engineer - Belfast
Job Summary
Are you a frontend engineer looking to work on genuinely cutting-edge technology, and to help build a brand-new UI team?
My client is a rapidly scaling unicorn, now valued at $3.8 billion after closing a $400 million Series C in October 2026. They're building a next-generation cloud security platform, using advanced eBPF-powered sensors to deliver real-time threat protection across modern cloud environments.
Their UI team is brand new, with 2-3 frontend engineers being hired, so you'll join at the very beginning and have a real hand in shaping how it works and the standards it sets. It's part of a major growth push in Belfast, with 20+ engineering roles open right now.
This is a dedicated frontend role, not a full-stack one. They're looking for engineers who genuinely want to specialise in frontend and are very technical.
Job Description
As a Frontend Engineer, you will be responsible for designing, building and evolving the frontend of a cloud-native security platform.
You will work closely with product managers, designers and backend engineers to deliver high-performance, scalable user interfaces, in a team that embraces modern, AI-assisted development.
Key responsibilities include:
- Designing and developing frontend components from concept through to production
- Leading frontend implementation across key product features
- Contributing to architectural and technical design decisions
- Championing product quality and user experience across the platform
- Defining and collaborating on API design with backend and platform teams
- Optimising application performance, scalability and reliability
- Participating in code reviews and design reviews to maintain engineering standards
Personal Specification
Essential Criteria
- 3+ years' experience in frontend engineering
- Strong commercial experience with React and TypeScript
- Solid understanding of core web technologies (HTML, CSS, JavaScript)
- Experience working with APIs and collaborating with backend teams
- Exposure to CI/CD pipelines and modern development practices
- A genuine wish to specialise in frontend, and a passion for building clean, high-performance user interfaces
Desirable Criteria
- Experience with WebGL or similar graphics / visualisation libraries
- Background in cloud-native or security-focused products
- Familiarity with modern frontend tooling and frameworks
- Experience working with design systems and responsive UI
Why This Role Stands Out
- Join a $3.8 billion unicorn during a major growth phase, with 20+ engineering roles open in Belfast
- Help build a brand-new UI team and set its direction from day one
- Work on a genuinely innovative cloud security platform
- Exposure to advanced technologies including eBPF and real-time threat detection
- A strong engineering culture with real technical ownership, and no egos
- The opportunity to influence both product direction and technical architecture
The Process
- A 4-stage interview process, including a hands-on coding round
Benefits
- Competitive salary (dependent on experience)
- 25 days' annual leave plus statutory holidays
- Equity and share options
- Hybrid working model, with 3 days per week in the office and sensible flexibility when you need it
- A high-impact, fast-growing company with clear progression opportunities
Skills:
Frontend React Security Engineer
WHJS1_NI