Senior Backend Software Engineer

Senior Software Engineer – UK Defence Programme Bath | Hybrid – typically 3 days onsite Permanent UK National / SC Clearance Eligible We’re looking for an experienced Senior Backend Engineer to join a major, multi-year technology transformation programme within UK defence. This is a hands-on engineering role with genuine technical ownership. You’ll be building and evolving a complex software platform and connecting it with a growing ecosystem of systems including data lakehouse technology, ERP platforms, optimisation engines and external partner platforms. Much of the technical landscape is still being designed, so this is ideal for an engineer who enjoys taking loosely defined requirements, shaping the solution and delivering it through to production. What You’ll Be Doing Design and build backend services and APIs.Develop complex integrations with ERP systems, data platforms and external technologies.Work primarily across Java, SQL and modern data/integration tooling.Design REST and event-driven integrations.Introduce Change Data Capture (CDC) and near-real-time data patterns where appropriate.Work with data warehouse/lakehouse environments.Make technical decisions around architecture, scalability, security and performance.Improve automated testing, CI/CD and observability.Take substantial pieces of engineering work from initial design through to production.Mentor engineers and contribute to wider backend engineering standards.Work with technical and non-technical stakeholders across a major defence programme. What We’re Looking For You’ll ideally be an experienced Senior Software Engineer with strong backend, integration and data experience. Key experience: Java or a comparable backend languageStrong SQLBackend services and API developmentREST and/or event-driven architectureSystems integrationData warehouse/lakehouse integrationCI/CD and automated testingObservability and production monitoringStrong system and data design knowledgeThird-party platform / ERP integration Experience with streaming technologies, Change Data Capture (CDC), data pipelines or near-real-time integrations would be particularly valuable. We’re looking for someone comfortable working with ambiguity who can understand the underlying problem, make pragmatic technical decisions and take ownership of delivering the solution rather than relying on a fully defined specification. Defence & Security Requirements Due to the nature of the programme, candidates must be UK nationals and eligible to obtain UK Security Clearance (SC). Existing active SC clearance would be advantageous but isn't essential for candidates who meet the eligibility requirements and are willing to undergo the clearance process. Experience within defence, central government, public safety or another regulated environment would also be beneficial. Location & Benefits Bath-based with hybrid working, typically around three days per week onsite at either the company office or customer locations. Benefits include: Competitive salary with annual reviews5% employer pension contributionPrivate healthcare including dentalEnhanced family leave25 days annual leave plus bank holidaysLife assuranceCycle-to-work schemeCompany social events Why Consider the Role? This is an opportunity to take genuine Senior-level ownership within a significant, long-term UK defence technology programme. You'll work on complex production systems and integrations while having the freedom to influence architecture, technology choices and engineering standards. It would particularly suit a backend engineer who wants to remain hands-on while solving challenging integration and data problems at scale. Interview Process The process is expected to include: Initial behavioural/hiring manager interviewHands-on programming sessionProduct-focused system design discussion The programming exercise can be completed in a suitable language such as Java, C#, TypeScript, Python or Go.