Principal Backend Engineer - Java
capco
UK - London
Posted Jan 9, 2026
- Other
- Tech & Engineering
Job description
#### **Principal Backend Engineer – Java** #### **Location: London (Hybrid) | Practice Area: Technology & Engineering | Type: Permanent** #### **Build scalable backend solutions that help shape the future of financial services.** #### **The Role** Capco is growing our Engineering team, and we’re looking for experienced Principal Backend Engineers with strong Java skills and a passion for delivering innovative solutions in financial services. As a Principal Backend Engineer at Capco, you’ll contribute to high-impact, client-facing projects and work with cloud-native technologies across different domains within Financial Services & Energy. You’ll collaborate with talented engineers, contribute to architecture and engineering decisions, and have access to industry-leading learning and development opportunities. You’ll also use approved AI tools, automation and AI-enabled engineering workflows where appropriate to improve development speed, quality and productivity, while applying human judgement, responsible AI guardrails and appropriate review. **What You’ll Do** - Build and deliver scalable backend services using Java 11, 17+, designing APIs and microservices for enterprise systems. - Work across cloud platforms, particularly AWS, applying cloud-native deployment techniques and contributing to architecture and solution design. - Develop robust automated test coverage across unit, component, integration, end-to-end and performance testing. - Collaborate with clients, product managers and engineers in agile teams to design, deliver and troubleshoot large-scale distributed systems. - Use approved AI tools, automation and AI-enabled workflows to support engineering activities such as development, testing, troubleshooting and documentation, with appropriate human review and responsible AI controls. **What We’re Looking For** - Expertise in Java 11, 17+ and Spring Boot, with experience designing and delivering large-scale enterprise backend systems. - Experience with cloud-native and distributed architectures, including microservices, event-driven patterns and CQRS, preferably deployed within AWS. - Experience with CI/CD, Infrastructure as Code such as CloudFormation, and SQL and NoSQL databases. - Experience with Kafka, Java streaming, automated testing and troubleshooting distributed systems. - Curiosity and practical experience using approved AI, GenAI or AI-enabled development tools to improve engineering productivity, with an understanding of human-in-the-loop review, responsible AI, guardrails and escalation where required. **Bonus Points For** - An appetite to contribute to the wider Capco business through activities such as thought leadership, supporting RFPs and coaching or mentoring engineering colleagues. - Proficiency with GitLab for CI/CD processes and experience writing automation test cases in Cucumber using Behaviour Driven Development (BDD). - AWS Certified Solutions Architect – Associate or Professional level certification. - Knowledge of security best practices, including IAM Roles and KMS. - Experience exploring responsible AI-enabled engineering practices, including automation or Agentic AI workflows, while maintaining appropriate review, auditability and human oversight. **Why Join Capco** - Deliver high-impact technology solutions for Tier 1 financial institutions. - Work in a collaborative, flat, and entrepreneurial consulting culture. - Access continuous learning, training, and industry certifications. - Be part of a team shaping the future of digital financial services. - Help shape the future of digital transformation across FS & Energy. We offer a competitive, people-first benefits package designed to support every aspect of your life: **Benefits** - **Core Benefits:** Discretionary bonus, competitive pension, health insurance, life insurance and critical illness cover. - **Mental Health:** Easy access to CareFirst, Unmind, Aviva consultations, and in-house first aiders. - **Family-Friendly:** Maternity, adoption, shared parental leave, plus paid leave for sickness, pregnancy loss, fertility treatment, menopause, and bereavement. - **Family Care:** 8 complimentary backup care sessions for emergency childcare or elder care. - **Holiday Flexibility:** 5 weeks of annual leave with the option to buy or sell holiday days based on your needs. - **Continuous Learning:** Your growth, your way – minimum 40 hours of training annually. Take your pick from workshops, certifications and e-learning. Plus, a Business Coach assigned from Day One provides one-to-one guidance to support your goals and accelerate your development. - **Healthcare Access:** Convenient online GP services. - **Extra Perks:** Gympass (Wellhub), travel insurance, Tastecard, season ticket loans, Cycle to Work, and dental insurance. **Inclusion at Capco** We’re committed to making our recruitment process accessible and straightforward for everyone. If you need any adjustments at any stage, just let us know – we’ll be happy to help. We value each person’s unique perspective and contribution. At Capco, we believe that being yourself is your greatest strength. Our #BeYourselfAtWork culture encourages individuality and collaboration – a mindset that shapes how we work with clients and each other every day. #LI-DNI