Senior C#. NET Developer Location: London (Hybrid) Contract: 6 months IR35: Inside IR35 Our client, a leading global investment bank, is looking for an experienced C#. NET Developer to join their team on a 6-month contract. This role is pivotal in modernising and supporting business-critical applications while contributing to greenfield development initiatives. Key Responsibilities Design, build, and maintain server-side and client-side applications using .NET Framework/Core, React/TypeScript, and relational databases (SQL Server, Oracle). Refactor legacy systems to reduce technical debt and improve performance. Implement modern security patterns (OAuth2/OpenID Connect, OWASP principles). Optimise database queries and schemas; ensure safe migrations. Participate in CI/CD processes, code reviews, and adhere to Change Management procedures. Collaborate with cross-functional teams and provide occasional out-of-hours support. Essential Skills Strong proficiency in .NET Framework/Core. Experience with SQL Server and Oracle performance tuning. Knowledge of secure SDLC practices and OWASP principles. Hands-on experience with CI/CD pipelines and troubleshooting across Windows Servers and databases. Excellent communication and problem-solving skills. Desirable React/TypeScript Certifications in Azure/AWS, CISSP, or DevOps. Familiarity with Docker/Kubernetes, observability practices, and API gateways. Exposure to greenfield projects and Python scripting. Apply now to join a dynamic team and work on cutting-edge projects within a global investment banking environment