Senior Java Developer in Belfast

At CGI, our Senior Java Developers play a vital role in building the secure, scalable digital solutions that help organisations innovate, transform and succeed.

As we expand our software engineering capability across the UK, you'll take ownership of developing high-quality applications that solve complex client challenges and deliver lasting business value. Working alongside talented engineers, architects and consultants, you'll explore modern technologies, influence technical decisions and champion creative approaches to software development.

With the support of our collaborative engineering community, you'll have opportunities to strengthen your expertise, mentor others and shape the future of digital services while making a meaningful impact across diverse industries.

CGI was recognised in the Sunday Times Best Places to Work List 2025 and has been named a UK ‘Best Employer’ by the Financial Times. We offer a competitive salary, excellent pension, private healthcare, plus a share scheme (3.5% + 3.5% matching) which makes you a CGI Partner not just an employee. We are committed to inclusivity, building a genuinely diverse community of tech talent and inspiring everyone to pursue careers in our sector, including our Armed Forces, and are proud to hold a Gold Award in recognition of our support of the Armed Forces Corporate Covenant.

Due to the secure nature of the programme, you will need to hold UK Security Clearance or be eligible to go through this clearance. This is a hybrid position.

Your future duties and responsibilities:

• Design, develop and deliver robust, scalable Java applications that support critical client services and digital transformation initiatives.
• Use Java and Spring Boot to build high-performing back-end solutions, applying modern engineering practices to ensure quality, security and reliability.
• Collaborate with clients and technical specialists to translate business requirements into effective software solutions.
• Work within supportive, multidisciplinary Agile teams where knowledge sharing, creative problem-solving and continuous improvement are encouraged.
• Provide technical guidance and mentorship to junior developers, champion coding standards and help foster a culture of collaboration and engineering excellence.
• Expand your technical capabilities and contribute to CGI's growing software development practice across the UK.

Key responsibilities:

• Build, enhance and maintain secure, scalable enterprise applications using Java and Spring Boot.
• Develop robust RESTful APIs and back-end services that support seamless integration and high performance.
• Work closely with clients, architects, engineers and cross-functional teams to translate requirements into reliable technical solutions.
• Apply software engineering best practices, automated testing, code reviews and version control to maintain high development standards.
• Provide technical guidance, coach junior developers and encourage knowledge sharing across the engineering community.
• Participate in sprint planning, daily stand-ups and retrospectives, using Jira and Confluence to support effective delivery.
• Identify opportunities to enhance application performance, maintainability and development processes.
• Build strong stakeholder relationships, communicate technical approaches clearly and contribute to successful client outcomes.

Required qualifications to be successful in this role:

• At least five years of professional Java development experience, with strong expertise in Spring Boot and building enterprise-level back-end applications.
• Confident working within Agile delivery teams, collaborating with clients and technical stakeholders.
• Ability to take initiative, solve complex technical challenges and support the development of others.

Essential qualifications and experience:

• Over five years of professional software development experience, with strong hands-on expertise in Java (version 8 or higher) and Spring Boot.
• Proven experience designing, developing and maintaining enterprise-level back-end applications.
• Strong understanding of object-oriented programming, software design principles and RESTful API development.
• Experience working in Agile environments, including Scrum ceremonies and iterative software delivery.
• Proficiency with development and collaboration tools, including Jira, Confluence and Git.
• Solid understanding of software engineering best practices, automated testing, code reviews and version control.
• Demonstrated ability to mentor junior developers, provide technical guidance and promote continuous improvement.
• Strong communication, stakeholder engagement and problem-solving skills.

Desirable qualifications and experience:

• Experience working within an IT consulting or client-facing environment.
• Familiarity with cloud platforms such as AWS, Microsoft Azure or Google Cloud Platform.
• Knowledge of Docker, Kubernetes and CI/CD pipelines.
• Exposure to microservices architecture and modern API integration approaches.

What you can expect from us:

Together, as owners, let’s turn meaningful insights into action. Life at CGI is rooted in ownership, teamwork, respect and belonging. Here, you’ll reach your full potential because you are invited to be an owner from day 1 as we work together to bring our Dream to life. That’s why we call ourselves CGI Partners rather than employees.

You’ll shape your career by joining a company built to grow and last. You’ll be supported by leaders who care about your health and well-being and provide you with opportunities to deepen your skills and broaden your horizons.