Senior .NET Developer

Senior .NET Developer (18-Month Fixed-Term)

The opportunity

A major New Zealand financial services organisation is undertaking a significant, long-term technology transformation, replacing a legacy core platform with a modern, future-ready solution.

As part of this programme, the organisation is implementing a modern core platform that will integrate with its wider products, payments, customer-facing systems and internal channels.

This Senior .NET Developer role will play an important part in building and modernising the services, APIs and integrations that support how customers and staff interact with the organisation.

The work is complex, highly visible and technically challenging. You’ll join a collaborative, cross-functional team working through ambiguity, solving difficult integration problems and helping shape systems that will be used for years to come.

As a Senior .NET Developer, you’ll take ownership across the full software development lifecycle, including analysis, solution design, development, testing, deployment and production support.

You’ll work closely with business stakeholders, analysts, architects, testers, operations teams and other developers to translate requirements into secure, reliable and maintainable software solutions.

The role involves delivering functionality across both existing and modern platforms, helping progressively modernise the technology environment while maintaining reliable services for customers and staff.

Key responsibilities

• Design and develop high-quality software solutions using C# and .NET.
• Build APIs, backend services and integrations supporting customer and internal systems.
• Help integrate a new core platform with a wider technology ecosystem.
• Interpret business requirements and Agile stories, considering related systems and delivery channels.
• Contribute to application architecture, technical design and engineering standards.
• Develop secure, reliable and highly available applications.
• Build and improve CI/CD pipelines, infrastructure-as-code and DevOps processes.
• Implement automated unit, integration and performance testing.
• Support non-functional testing across availability, performance and security.
• Develop monitoring, telemetry, dashboards and alerting.
• Investigate production issues and perform root-cause analysis.
• Maintain and improve the quality, resilience and architecture of existing systems.
• Collaborate across engineering teams to ensure solutions work effectively across multiple systems.
• Share knowledge, support other developers and contribute to continuous team improvement.
• Challenge existing approaches and bring new ideas into the programme.

What you’ll bring

• At least seven years of commercial software development experience.
• Strong experience with C# and .NET.
• Experience designing and developing end-to-end software solutions.
• Strong SQL knowledge.
• Experience with unit, integration and performance testing.
• Experience with CI/CD, DevOps practices and infrastructure-as-code.
• Experience working in cross-functional Agile teams.
• The ability to make sound technical and architectural decisions.
• Strong analytical and problem-solving capability.
• Experience working with complex integrations and interfacing systems.
• A strong focus on software security, reliability and maintainability.
• The confidence to work through ambiguity and influence technical decisions.

Useful experience:

• AWS.
• REST and gRPC services.
• Highly available or business-critical systems.
• Application performance and security.
• Financial services or other regulated environments.
• Modernisation of legacy systems.
• Coaching or mentoring other developers.

Why consider this role? This is an opportunity to work on a large-scale, long-term technology transformation with genuine technical complexity and business impact.

You’ll have the opportunity to work on business-critical systems, influence technical design and engineering practices, work across modern APIs, cloud, DevOps and integration technologies, and take genuine end-to-end ownership of solutions.