Frontend Software Engineer

iO Associates; Greater London; Hybrid; GBP 65,000 - 90,000; Full time

Job summary

iO Associates is seeking a Frontend Software Engineer for a hybrid London role, crafting complex, high-performance web applications to visualise and navigate data. You will own core frontend components, extend them for customer-specific workflows across sectors, and move prototypes from concept to production with robust, reusable abstractions.

A strong eye for UX, accessibility and responsive design, plus experience with React, TypeScript and modern tooling, will help you thrive in a fast-paced,

Qualifications

• Frontend engineer with experience building complex, high‑performing web apps for data visualisation.
• Strong React/TypeScript proficiency and modern frontend tooling experience.
• Experience with real‑time data patterns and WebSockets is desirable.
• Experience with 3D data visualisation and related libraries is a plus.

Responsibilities

• Build core frontend components and interfaces, and extend them for customer‑specific workflows across sectors.
• Collaborate across teams to visualise and navigate data with robust, reusable abstractions.
• Rapidly turn prototypes into production code while prioritising performance and maintainability.

Skills

React

TypeScript

Vite

Tailwind CSS

gRPC/protobuf

3D visualization

WebSockets

Testing (Vitest/Jest/Playwright)

Storybook

UX/UI accessibility

Data visualization

Job description

Frontend Software Engineer - Hybrid - London - Hiring across all levels

Our Client

Our client's platform connects to existing cameras and sensors to detect threats, retrace events, and surface real-time insights - all without replacing a single device. They help teams reduce risk, cut costs, and grow revenue through better visibility, faster decisions, and fewer blind spots.

Their culture is built on a foundation of radical candour and mutual trust. They recognise that being an industry leader requires more than just building exceptional products - it requires empowering a team of exceptional people. Individually, the team operates with high autonomy; collectively, they're unified by a shared drive to achieve their mission through a commitment to excellence.

The Role

They're looking for a frontend engineer with experience building complex, performant, dynamic web applications for visualising and navigating data.

You'll be responsible for building core frontend components and interfaces, as well as extending them to drive customer-specific workflows across a variety of sectors.

This is a high-impact role suited to someone who can rapidly bring a prototype from concept to execution while choosing robust, reusable abstractions.

Key Skills

• Core technologies: React, TypeScript, Vite, Tailwind CSS, gRPC/protobuf
• 3D (desirable): Experience visualising data in 3D (e.g. Three.js, React Three Fiber, WebGL, Deck.gl)
• Real-time data flows: Comfortable working with real-time data and async patterns (WebSockets, workers)
• Writing testable, reusable code: Vitest/Jest/Playwright, Storybook, design systems
• Data visualisation: Presenting complex data intuitively; geospatial experience is a plus
• UX/UI (desirable): A strong sense of user experience, accessibility and visual design is a plus