Principal Java Software Engineer in London
Job Description
Principal Software Engineer
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- Salary to £80k, poss. higher for their ‘Unicorn’ candidate
- Role can be based remotely, as long as you can occasionally travel to London for client work (travel expenses paid) - approx. once a month.
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NB: Please only apply if you are a UK , have resided in the UK for the past 5 years and are prepared to go through UK SC Security Clearance. Proof of ID will be required prior to interview.
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This role is with a growing is a technology consultancy. This is a hands-on principal engineering role: architecture ownership across multiple services, technical leadership across teams, and direct contribution to engineering standards and hiring. Their successful candidate will be writing code as well as setting direction - this is not a purely architectural or management position. Current delivery is a Java/Spring Boot microservices platform on AWS EKS, with a Next.js frontend and Camunda-based process orchestration.
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Essential
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Experience level: 10+ years minimum, principal or staff grade equivalent.
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Backend and cloud:
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Java 17 or 21, at expert level - modern features
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Spring Boot in depth: security, transaction management, async/reactive
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Microservices architecture design - has designed services from scratch
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Kubernetes and Docker in production (not local development use)
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AWS, hands-on: EKS, Lambda, S3, RDS, EventBridge
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CI/CD pipeline ownership
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Automated testing discipline: JUnit, Mockito, integration testing, TDD or BDD
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Frontend:
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Held a lead or tech lead role on frontend development in React. Leadership must have been over React work itself.
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Understands and has implemented FFE/BFE separation - the split between the presentation layer (components, styling, client state) and the frontend's own server-side tier (data aggregation for the UI, session and auth handling, server-side rendering, API route composition).
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Leadership:
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Architecture ownership across multiple systems
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Cross-team technical leadership
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Track record of influencing engineering standards, technology choices, or hiring
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Evidence of growing other engineers
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Security clearance: UK SC clearance required. Active clearance strongly ; eligible candidates considered - must be a UK with 5+ years continuous UK .
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Desirable:
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Camunda 8 / BPMN process orchestration
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Next.js specifically (App Router, server components, route handlers)
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Terraform or other infrastructure-as-code, to module-authoring level
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React Native or equivalent — building native mobile from a React codebase
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Design system or component library ownership
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Consultancy or client-facing delivery background
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Open-source contributions, conference talks, or published technical writing
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Polyglot beyond Java
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Other Stuff
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NB: for non-UK Citizens; we cannot accept applications from anyone requiring sponsorship (now or in the future) for UK permanent employment status. If you are utilising a work visa this must allow you to work in the UK unrestricted for at least the next 5 years.
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Profile 29 recruitment keywords: Java Spring Boot Microservices Kubernetes Docker AWS EKS Lambda S3 RDS EventBridge CI/CD Junit Mockito integration testing TDD BDD React Camunda BPMN Next.js Terraform lead senior manage manager director remote London hybrid developer engineer
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