Lead Full-Stack Developer

Lead Full Stack Developer
Rate: Up to 650/day (Outside IR35)
Duration: 6 months initially
Location: Hybrid - Milton Keynes / Remote
Clearance: SC Cleared

Overview
An exciting opportunity for a Lead Full Stack Developer to join a small, high-performing tech company supporting a major UK government programme. You'll play a key role in the development and evolution of a cutting-edge, AI-enabled digital service used across multiple government departments.
This role combines hands-on development with technical leadership, working closely with architects, product stakeholders, and client teams to deliver secure, scalable software solutions.

Responsibilities
Front End

• Design and build modern, responsive user interfaces
• Develop using React, TypeScript, JavaScript, HTML, CSS
• Drive strong UX and cross-browser compatibility

Back End

• Design and develop APIs and services
• Build server-side logic using Java (Spring Boot)
• Contribute to overall application architecture

Data & DevOps

• Design and maintain relational databases (PostgreSQL preferred)
• Implement CI/CD pipelines (e.g. GitHub Actions, Jenkins)
• Deploy and operate services in cloud environments (AWS, Azure or GCP)
• Use containerisation tools such as Docker

Quality & Collaboration

• Lead and participate in code reviews
• Write unit, integration and end-to-end tests (JUnit, Testcontainers, Vitest, Storybook)
• Maintain clear technical documentation
• Work closely with product, architecture and delivery teams
• Embed security best practices (auth, access control, secure data handling)

Essential Skills & Experience

• Strong experience delivering complex full-stack applications
• Commercial expertise in Java plus at least one other back-end language (ideally Python)
• Solid experience with React and modern front-end tooling
• Strong API design and integration experience
• Good working knowledge of Linux and Windows environments
• Proven problem-solver with strong analytical skills
• Experience with relational databases, ideally PostgreSQL
• Comfortable working in small, fast-moving delivery teams
• Able to commute to Milton Keynes as required