Frontend Software Engineer

iO Associates; Islington (MA); Hybrid; USD 81,000 - 122,000; Full time

Job summary

Our Client in London is seeking a frontend software engineer to build complex, performant web applications for visualising and navigating data. You will develop core frontend components and adapt them to support diverse customer workflows across industries.

The role requires rapid prototyping to execution with robust, reusable abstractions, and a strong emphasis on UX, accessibility and visual design.

Qualifications

• Frontend engineer with experience building complex, performant, dynamic web applications for visualising and navigating data.
• Responsible for building core frontend components and interfaces, and extending them to drive customer-specific workflows across sectors.
• High-impact role: bring a prototype from concept to execution with robust, reusable abstractions.

Responsibilities

• Build core frontend components and interfaces for data visualization platforms.
• Extend components to support customer-specific workflows across multiple sectors.
• Collaborate with design and backend teams to ensure performance and accessibility.

Skills

React

TypeScript

Vite

Tailwind CSS

gRPC/protobuf

Three.js

React Three Fiber

WebGL

Deck.gl

WebSockets

Worker Threads

Vitest/Jest/Playwright

Storybook

Design Systems

Geospatial

UX/UI

Accessibility

Tools

Three.js

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