Senior Full Stack Java/React Engineer - Contract

Role: Senior Full Stack Engineer

London 1x a week

Rate: Up to £600 per day - Outside IR35

Length: 6 Months (Good chance of extension)

About the Role

We are seeking a Senior Java / React Full Stack Developer to join our client on a contract basis as a hands-on engineering consultant within a Solutions Engineering team.

This role centres on modernising large-scale, complex software systems, reducing technical debt, and improving delivery speed and reliability. You will work closely with client engineering teams, alongside platform and test engineers, helping to introduce modern development practices and AI-assisted engineering techniques to enhance productivity.

You will report to a Principal Software Engineer and play a key role in promoting and embedding best practices within delivery teams.

About You

You are an experienced, hands-on Java/React developer who enjoys working on complex systems and influencing how software is designed, built, and evolved.

You bring:

• Strong experience with React and modern front-end development

• Strong experience with Java backend development (Spring, MongoDB)

• A solid grounding in Domain-Driven Design (DDD)

• Experience working with microservice-based architectures

• Full-stack awareness and the ability to collaborate across disciplines

• Interest or experience in AI-assisted development to improve code quality and delivery speed

• Confidence working directly with clients and guiding technical decisions

Responsibilities

• Design and deliver modern Java/React applications within complex environments

• Improve development workflows, testing approaches, and overall developer productivity

• Support the decomposition of monolithic systems into well-defined services

• Apply DDD principles to improve maintainability and system clarity

• Collaborate with platform and test engineers to deliver end-to-end solutions

• Support teams in adopting modern tooling and AI-assisted development practices

• Act as a senior consultant within delivery teams, influencing engineering best practices

Technical Skills

Core Technologies

• Java / Spring

• React

• XML / HTML / CSS

• MongoDB

• Playwright

• Docker / Kubernetes

• Maven

• GitLab

We are an equal opportunities employer and welcome applications from all suitably qualified persons regardless of their race, sex, disability, religion/belief, sexual orientation or age.