The Lead Associate - Back End Engineer is a hands-on senior engineering role, equivalent in scope and expectations to a UK Senior Engineer. The role is responsible for building high-quality back-end software solutions across Consulting & Technology estate. The role provides strong squad-level technical contribution across the .NET ecosystem, including C#, ASP.NET Core, clean architecture, APIs, domain modelling, SQL Server, Azure, and automated engineering practices. Working closely with architects and lead engineers, the role helps translate technical direction into maintainable implementation, supports engineering standards, and raises overall delivery quality through good engineering practice. This role is ideal for an experienced back-end engineer who can operate independently, support less experienced developers, contribute to technical design, and deliver robust services in Agile engineering squads. Key Responsibilities Back End Design & Development Design, develop, and maintain high-quality .NET applications and services aligned to agreed architecture and squad delivery priorities. Implement APIs, domain services, background workers, and integration components using clean architecture principles. Write clean, maintainable, secure C# code following SOLID principles, Domain-Driven Design concepts, design patterns, and agreed engineering standards. Develop data access layers, persistence strategies, and SQL Server / Entity Framework solutions that support performance, reliability, and maintainability. Build containerised and event-driven components where appropriate, supporting scalable and resilient platform capabilities. Engineering Quality, Testing & DevOps Create and maintain automated tests across unit, integration, contract, and service layers, applying TDD where appropriate. Contribute to CI/CD pipelines, build quality gates, automated deployment, environment configuration, and release readiness. Support observability, resilience, logging, monitoring, alerting, and performance tuning for back-end applications and services. Apply secure coding practices across APIs, authentication, authorisation, data handling, dependency management, and service-to-service communication. Technical Contribution & Mentoring Act as a senior engineer within the squad, modelling good engineering discipline, ownership, and pragmatic problem-solving. Support and mentor junior and mid-level developers through code reviews, pairing, design discussion, and constructive technical guidance. Contribute to shared back-end standards, templates, service patterns, and clean architecture practices. Support recruitment and onboarding activities where back-end engineering input is required. Problem Solving & Support Diagnose, troubleshoot, and resolve complex back-end issues affecting delivery, quality, performance, integration, or production stability. Work with Architects, Lead Engineers, Front End Engineers, QA, and Platform Engineers to resolve cross-cutting technical problems. Contribute to improvements in shared back-end libraries, frameworks, and platform components where required. Collaboration & Stakeholder Engagement Work closely with Architects, Product Owners, Platform Engineers, Front End Engineers, and QA teams to ensure technical solutions meet business and user needs. Participate actively in Agile ceremonies, contributing to planning, refinement, retrospectives, technical discovery, and continuous improvement. Continuous Improvement & Innovation Identify practical opportunities to improve developer experience, service quality, maintainability, resilience, and delivery effectiveness. Keep up to date with relevant .NET, Cloud technologies, clean architecture, testing, and integration developments. Contribute to continuous learning and engineering improvement across the squad and wider engineering community. Skills, Knowledge and Expertise Mandatory: 8–12+ years of professional software engineering experience, or equivalent capability demonstrated through delivery experience. Strong relevant experience delivering modern .NET services, APIs, and back-end applications in commercial or enterprise environments. Bachelor’s degree in Computer Science, Engineering, Technology, or equivalent practical experience. Knowledge, Skill and Ability C#, .NET, ASP.NET Core, Web APIs, background services, and modern back-end engineering patterns. Clean Architecture, SOLID principles, Domain-Driven Design, design patterns, and maintainable service boundaries. REST APIs, OpenAPI/Swagger, authentication, authorisation, API versioning, and secure integration patterns. SQL Server, Entity Framework Core, data modelling, query optimisation, and transactional consistency. Microservices, containerised applications, event-driven architecture, messaging, and integration patterns. Azure services, CI/CD pipelines, Terraform or other infrastructure-as-code tooling, and DevOps practices. Automated testing including TDD, unit, integration, contract, and performance testing approaches. Essential Requirement 8–12+ years of professional software engineering experience, or equivalent capability demonstrated through delivery experience. Strong hands-on proficiency in C#, .NET, ASP.NET Core, and back-end service development. Good understanding of clean architecture, SOLID principles, Domain-Driven Design concepts, and maintainable service design. Experience designing and delivering REST APIs, service components, and integration patterns. Strong SQL Server and Entity Framework Core capability. Automated test practices across unit, integration, and contract testing. Experience with CI/CD pipelines, DevOps tooling, Azure services, and infrastructure-as-code practices. Secure coding practices and familiarity with OWASP principles. Nice to have • TypeScript, JavaScript, React, HTML5, CSS3, responsive design, and front-end build tooling such as Vite or Webpack.