Senior Software Enginner

Lead Backend Software Engineer – Data Services Federated Data Services | Distributed Systems | Apache Spark | DataFusion | Python | Kubernetes Location: London (2 days per week onsite) Rate: £700–£800 per day (Outside IR35) Duration: Initial 6-month contract with likely extension Overview We're looking for an experienced Lead Backend Software Engineer to join a high-profile programme building secure, cloud-native data services that will support data-driven research and innovation at national scale. This is a founding engineering role, offering the opportunity to shape the architecture, engineering standards, and core data services from the ground up. Working closely with the Engineering Manager and a small team of senior engineers, you'll establish the technical foundations for a complex federated data platform operating within a highly regulated environment. We're looking for someone who enjoys building from first principles, thrives in ambiguity, and can balance strategic architectural thinking with hands-on software engineering. This role is centred around designing and building distributed data services rather than traditional application development. Role & Responsibilities • Lead the design and development of scalable, cloud-native data services supporting a federated platform. • Define architectural patterns, engineering standards, and best practices that will scale across the wider organisation. • Design and build distributed server-side services using modern software engineering practices. • Architect and develop federated data services capable of securely querying and processing data across multiple environments. • Design high-performance data processing and streaming workflows using technologies such as Apache Spark, Apache DataFusion, or similar distributed query frameworks. • Design and implement Kubernetes-based services and containerised workloads. • Build secure APIs and backend services supporting authentication, authorisation, governance, and audit requirements. • Contribute to the design of distributed systems, data pipelines, and platform architecture. • Establish CI/CD pipelines, Infrastructure as Code, automated testing, and deployment practices. • Evaluate and integrate open-source technologies and distributed data frameworks. • Mentor engineers and promote engineering excellence across the team. • Work closely with architecture, product, security, and external stakeholders. Skills & Experience Essential • Experience as a Lead Engineer, Principal Engineer, Staff Engineer, Software Architect, or similar senior technical role. • Strong server-side software engineering experience, with flexibility across programming languages such as Python, Java, Go, Scala, C#, or similar. • Experience designing and building distributed data services or large-scale backend platforms. • Experience with Apache Spark, Apache DataFusion, Trino, Presto, or similar distributed data processing technologies. • Strong architecture and design experience across distributed systems and data services. • Experience designing scalable data processing or data streaming workflows. • Experience building cloud-native applications on AWS, Azure, or GCP. • Experience with Kubernetes, Docker, and containerised environments. • Experience building and operating CI/CD pipelines and Infrastructure as Code. • Strong understanding of distributed systems, scalability, resilience, and secure-by-design principles. • Comfortable making architectural decisions within evolving, fast-paced environments. • Excellent communication skills with the ability to work across technical and non-technical teams. Desirable • Experience building federated data services or federated data platforms. • Experience within healthcare, life sciences, research, government, or other highly regulated environments. • Knowledge of Trusted Research Environments (TREs), Secure Data Environments (SDEs), or similar secure data platforms. • Experience with data governance, metadata services, data catalogues, or secure data access models. • Exposure to event-driven architectures and streaming technologies such as Kafka, Flink, or Spark Streaming. • Experience evaluating or contributing to open-source technologies.