Front-End Javascript Developer

Capgemini; City Of London; On-site; GBP 60,000 - 80,000; Full time

Job summary

A leading technology transformation partner in the UK is seeking a skilled Senior / Lead Front-end JavaScript Developer to join their Experience Engineering team. The successful candidate will lead a public sector web application project, requiring strong skills in HTML, CSS, and JavaScript, as well as experience in cloud-native development and mentoring developers. This role offers the chance to work on impactful solutions with a diverse team.

Qualifications

• Experience leading development teams and providing mentorship.
• Ability to write robust and scalable queries and operations.
• Excellent problem-solving skills and critical thinking.

Responsibilities

• Lead the development of a web application for public sector programme.
• Provide mentorship and technical leadership to developers.
• Collaborate with cross-functional teams and conduct code reviews.

Skills

HTML5, CSS3, and JavaScript (ES6+)

Express.js

Nunjucks

GOV.UK Design System

GOV.UK CASA UI framework

MongoDB

NoSQL

TypeScript

Cloud‑Native development on AWS

CI/CD pipelines

Git

Web standards and accessibility

Job description

About the job you're considering

We are seeking a highly skilled and experienced Senior / Lead Front-end JavaScript Developer to join our Experience Engineering team. In this role, you will lead the development of an impactful web application for a public sector programme, ensuring high performance, scalability, and maintainability. You will work closely with cross-functional teams to deliver engaging solutions that meet our client's needs.

Your role

• Provide technical leadership and mentorship to a team of developers, guiding them through best practices and ensuring high-quality code.
• Design, develop, and maintain front‑end components of web applications using HTML, CSS & JavaScript.
• Collaborate with architects and other developers to design robust, scalable, and secure architectures for new projects and enhancements to existing systems.
• Lead and participate in agile development processes, including sprint planning, daily stand‑ups, and retrospectives.
• Conduct thorough code reviews to ensure code quality, performance, and adherence to best practices.
• Continuously improve our teams' development processes, tools, and techniques to enhance productivity and product quality.
• Work closely with clients and internal teams to understand requirements, provide technical guidance, and deliver solutions that exceed expectations.
• Stay up to date with the latest industry trends and technologies, and drive continuous learning and innovation within the team.

Your skills and experience

• Proficiency in HTML5, CSS3, and JavaScript (ES6+).
• Proven experience of Express.js and Nunjucks.
• Experience using the GOV.UK Design System.
• Familiarity with the GOV.UK CASA UI framework.
• Experience with MongoDB and NoSQL variants, writing robust and scalable queries and operations.
• Experience with TypeScript and modern development tools and practices.
• Knowledge of Cloud‑Native development on the AWS Platform (IAM, SQS, S3, Secrets Management, KMS).
• Familiarity with CI/CD pipelines and DevOps practices.
• Experience with version control systems (Git).
• Understanding of web standards, accessibility, performance, and development best practice.
• A track record in a lead or senior developer role, with experience of mentoring and guiding development teams.
• Excellent problem‑solving skills and the ability to think critically and creatively.

Your Security Clearance

To be successfully appointed to this role, it is a requirement to obtain Security Check (SC) clearance. To obtain SC clearance, the successful applicant must have resided continuously within the United Kingdom for the last 5 years, along with other criteria and requirements. Throughout the recruitment process, you will be asked questions about your security clearance eligibility such as, but not limited to, country of residence and nationality. Some posts are restricted to sole UK Nationals for security reasons; therefore, you may be asked about your citizenship in the application process.

Why you should consider Capgemini

Growing clients' businesses while building a more sustainable, more inclusive future is a tough ask. When you join Capgemini, you'll join a thriving company and become part of a diverse collective of free‑thinkers, entrepreneurs and industry experts. We find new ways technology can help us reimagine what's possible. It's why, together, we seek out opportunities that will transform the world's leading businesses, and it's how you'll gain the experiences and connections you need to shape your future. By learning from each other every day, sharing knowledge, and always pushing yourself to do better, you'll build the skills you want.

About Capgemini

Capgemini is a global business and technology transformation partner, helping organisations to accelerate their dual transition to a digital and sustainable world, while creating tangible impact for enterprises and society. It is a responsible and diverse group of 340,000 team members in more than 50 countries. With its strong over 55‑year heritage, Capgemini is trusted by its clients to unlock the value of technology to address the entire breadth of their business needs.