Senior Software Engineer - .NET

Job description

We are looking for an experienced Senior .NET Developer (C#) to join the Acquisitions & Originations engineering team within Experian's Credit & Verification Services business. The Domain The Acquisitions & Originations team develops and provides level 3 support for the Delphi Select and Evaluate platforms, which are used across the Acquisitions and Originations business.

These are complex, configuration-driven, multi-client systems

each client (bank, lender or other financial institution) runs its own decisioning strategies, rules and data configurations on a shared codebase. Clients depend on these systems to make real-time lending and origination decisions, so reliability, data integrity and controlled release processes are central to the role. This is a hybrid, Nottingham based role (40% in the office) reporting to the Lead Developer.

Key Responsibilities

Own features end-to-end across the full software development lifecycle: requirements analysis, technical design, development, unit and integration testing, code review, deployment and post-release support. Design, develop and maintain scalable, maintainable C#/.NET services and components within a complex, multi-client system, ensuring changes are safe across all client configurations. Translate high-level and client-specific requirements into robust technical designs, in collaboration with the Technical Lead, Architects, Business Analysts and Product Owners.

Maintain and improve automated test coverage (unit, integration and regression) to support safe, frequent releases into a live multi-client platform. Contribute to and help evolve CI/CD pipelines (Git, Jenkins) Identify and help remediate technical debt, and contribute to ongoing modernisation of the platform, including its migration towards cloud-native (AWS) architecture. Mentor Intermediate and Junior developers, sharing technical knowledge and supporting their growth, including in the effective use of AI-assisted development tools.

Qualifications

Required Skills / Knowledge Strong expertise in .NET Core / .NET Framework and C#, including object-oriented design and common design patterns. Proven experience across the full software development lifecycle, ideally supporting a live, business-critical production system. Solid experience with SQL Server / T-SQL, including writing and optimising queries and stored procedures against production data. Experience designing and consuming RESTful APIs, and working with service-oriented or microservice architectures.

Practical experience with unit and integration testing frameworks (e.g. xUnit, NUnit or MSTest). Experience with version control and CI/CD tooling (e.g. Git, Jenkins, or equivalent). Direct experience working in a Scrum or other Agile team, including sprint planning, stand-ups and retrospectives. Hands-on, everyday experience using AI-assisted development tools (e.g. GitHub Copilot, Cursor, Claude, ChatGPT) for tasks such as code generation, refactoring, test writing, debugging and documentation Useful Skills (beneficial, not mandatory) Exposure to AWS services (e.g.

DynamoDB, S3, EC2 ) or a strong interest in developing cloud skills as the platform migrates to AWS. Experience with Infrastructure as Code (e.g. Terraform, CloudFormation). Knowledge of containerisation (Docker, Kubernetes). Experience in financial services, lending, credit decisioning or a similarly regulated domain. Exposure to front-end technologies such as React or modern JavaScript/TypeScript. Experience working with configuration-driven or rules-engine-based systems.