Principal Java Engineer - Microservices / Event-Driven ArchitectureAt a GlancePrincipal-level Java engineering role at a high-growth scaleupEvent-driven microservices architecture - leading legacy monolith decompositionFlexible / hybrid workingSalary: 75-85kArchitecture ownership, mentorship, and real engineering leadership from day oneAbout the CompanyOur 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 RoleThis 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 ResponsibilitiesDesign and build modern Java microservices within an event-driven architectureLead the decomposition of legacy monolith systems into scalable, decoupled servicesDrive best practices across code quality, system design, and engineering deliveryDefine and own architecture standards that scale with the businessProvide mentorship and technical leadership across the team - from pairing to code reviewCollaborate closely with product managers, designers, and engineering peersHelp the business scale safely and efficiently through pragmatic, commercially grounded engineering decisionsWhat You'll NeedEssential6+ years' commercial Java development experience, including deep knowledge of microservicesProven experience migrating monolithic systems into modern service architecturesStrong grasp of system design, distributed systems, and cloud-native developmentExperience mentoring or leading engineers in a high-growth environmentA technical mindset grounded in real-world delivery and commercial impactGreat communication skills and a collaborative, team-first approachRight to work in the UKNice to HaveExperience working in a scaleup or product-led engineering environmentFamiliarity with safety-critical or regulated domainsWhy Apply?Generous annual leave entitlementESOP scheme - share in the growth you help createPrivate health cover including dental and opticalCycle-to-work and tech schemeFlexible working environmentWork with a mission-led scaleup solving real-world safety problemsGenuine architectural ownership and technical leadership at Principal levelInterested?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-drivenBenefits:Work From Home OptionsWHJS1_NI