Principal Java Engineer - Microservices / Event-Driven Architecture At a Glance Principal-level Java engineering role at a high-growth scaleup Event-driven microservices architecture - leading legacy monolith decomposition Flexible / hybrid working Salary: 75-85k Architecture ownership, mentorship, and real engineering leadership from day one About the Company Our client is a mission-led scaleup solving real-world safety problems at scale. They're building a modern, cloud-native backend to support their growth, and their engineering team is focused on doing things properly - clean systems, strong practices, and pragmatic decision-making. With an ESOP scheme on the table, this is a business that wants its engineers to grow with it. The Role This is a Principal-level engineering position at the heart of a significant technical evolution. You'll join a high-calibre backend team delivering high-scale, event-driven microservices, and take ownership of the architecture and engineering standards that will underpin the business as it scales. This goes well beyond hands-on Java development - you'll be mentoring engineers, defining long-term architectural direction, and leading the decomposition of legacy systems into modern, decoupled services. The right person is a pragmatic engineer who loves clean systems, builds for scale, and takes genuine satisfaction from helping others grow. Key Responsibilities Design and build modern Java microservices within an event-driven architecture Lead the decomposition of legacy monolith systems into scalable, decoupled services Drive best practices across code quality, system design, and engineering delivery Define and own architecture standards that scale with the business Provide mentorship and technical leadership across the team - from pairing to code review Collaborate closely with product managers, designers, and engineering peers Help the business scale safely and efficiently through pragmatic, commercially grounded engineering decisions What You'll Need Essential 6 years' commercial Java development experience, including deep knowledge of microservices Proven experience migrating monolithic systems into modern service architectures Strong grasp of system design, distributed systems, and cloud-native development Experience mentoring or leading engineers in a high-growth environment A technical mindset grounded in real-world delivery and commercial impact Great communication skills and a collaborative, team-first approach Right to work in the UK Nice to Have Experience working in a scaleup or product-led engineering environment Familiarity with safety-critical or regulated domains Why Apply? Generous annual leave entitlement ESOP scheme - share in the growth you help create Private health cover including dental and optical Cycle-to-work and tech scheme Flexible working environment Work with a mission-led scaleup solving real-world safety problems Genuine architectural ownership and technical leadership at Principal level Interested? Feel free to apply via the link below or reach out to Ryan Quinn directly on LinkedIn for a confidential conversation. We represent the largest selection of technology roles of any recruitment firm in Northern Ireland, if this one isn't the right fit, we're always happy to meet and talk through where you want to go in 2026. Skills: Java Microservices AWS Event-driven Benefits: Work From Home Options ADZN1_NI