Senior .NET Developer

* 12-month Contract * Sydney CBD – Hybrid 3 days on-site * Opportunity of converting to permanent We are seeking an experienced Senior .NET Developer to join a large enterprise environment, working on the development, enhancement and modernisation of business-critical applications and services. This is a hands-on engineering role focused on building scalable APIs, integrating existing platforms and delivering new capabilities within a complex enterprise technology landscape. Key Responsibilities * Design, develop and enhance applications and APIs using C# and .NET. * Build and integrate RESTful APIs and microservices across existing enterprise platforms. * Develop cloud-native solutions leveraging AWS services. * Work with SQL Server for database integration, performance and optimisation. * Collaborate with architects, product owners and engineering teams to deliver business solutions. * Contribute to technical design, code reviews, troubleshooting and continuous improvement. **Skills & Experience** * Strong commercial experience with C# / .NET development. * Proven experience designing and integrating REST APIs and microservices. * Hands-on experience with AWS cloud services. * Strong SQL Server development and optimisation skills. * Experience working within large, complex enterprise environments, particularly across established applications, service domains and API ecosystems. * Strong understanding of software engineering principles, design patterns and Agile delivery. * Excellent communication skills and ability to collaborate across technical and business teams. Must have * 8+ years professional experience * Banking/Financial Services background * Australian Citizenship or Permanent Residency An opportunity to work within a mature enterprise technology environment, contributing to the evolution of established platforms while delivering modern, scalable solutions. You’ll work alongside experienced engineering teams on complex integration challenges, platform enhancements and ongoing technology modernisation.