Senior Frontend developer

Location: City of London

Senior Frontend Developer (Contract)

Overview

We are looking for a talented Senior Frontend Developer to join a high-performing engineering team working on business-critical customer and colleague applications. This is an opportunity to contribute to modern web applications, deliver impactful features, and help drive the evolution of frontend platforms in a collaborative and fast-paced environment.

You'll work closely with designers, backend engineers, product teams, and platform specialists to build scalable, maintainable, and high-quality solutions using modern frontend technologies.

Contract Details

Role:
Senior Frontend Developer
Contract Type:
Inside IR35

Start Date:

ASAP (flexible for the right candidate)
Duration:
Until the end of 2026 with potential extension
Rate:
Up to £650 per day
Working Pattern:
Hybrid - 1 day per week on-site in London (Thursdays)

Hours:

40 hours per week

The Role

You will primarily work on an established telephony platform used by customer-facing teams to manage inbound and outbound communications. The role involves delivering new features, supporting existing functionality, and helping modernise frontend systems as part of ongoing platform transformation projects.

Responsibilities include:

Taking ownership of frontend feature delivery from design through to production
Building and maintaining React and Next.js applications
Developing clean, scalable, and well-tested Type Script code
Supporting the migration and modernisation of existing frontend platforms
Working with shared component libraries and design systems
Debugging production issues and improving application performance
Contributing to CI/CD processes and deployment pipelines
Participating in code reviews and mentoring less experienced developers
Collaborating with Product, Design, Backend and Platform teams
Making pragmatic technical decisions that balance delivery, quality, and maintainability

Technology Stack

React
Next.js (App Router)
Type Script
Tailwind CSS
Component Design Systems
Playwright
Jest
Vitest
Git-based CI/CD pipelines
Monitoring and observability tools
Cloud-based infrastructure environments

Essential Skills & Experience

Strong commercial experience with React
Proven expertise with Next.js
Advanced Type Script development experience
Senior-level frontend engineering experience
Experience working within large-scale frontend applications
Strong testing background using tools such as Playwright, Jest, and Vitest
Ability to work independently while collaborating effectively within agile squads
Experience troubleshooting and resolving production issues
Excellent communication and stakeholder management skills

Desirable Experience

Experience with telephony or contact-centre applications
Knowledge of Twilio integrations
Experience working with design systems and component libraries
Exposure to cloud-native environments and modern Dev Ops practices
Previous experience mentoring developers and supporting technical growth within teams

What We're Looking For

We're seeking a senior engineer who enjoys solving complex frontend challenges, delivering high-quality customer-focused solutions, and working within a collaborative engineering culture. You'll be comfortable owning features end-to-end, contributing to technical discussions, and helping shape the future direction of modern web applications.

This role would suit someone who combines strong technical expertise with a practical, delivery-focused mindset and a passion for building exceptional user experiences.

Rullion celebrates and supports diversity and is committed to ensuring equal opportunities for both employees and applicants