Senior Fintech Backend Engineer - Scale & API Reliability

North Island - Auckland Central Auckland; Auckland; On-site; NZD 120,000 - 150,000; Full time

Job summary

Crossware in Auckland is seeking a Senior Backend Developer to join our team at the office. You will design, build, and maintain scalable C#/.NET backend services and APIs that power real-world applications used by thousands of customers.

You will contribute to architecture, ensure performance and reliability, and collaborate with engineers, product, and support teams. Experience with AKS, Docker, Azure, and CI/CD is highly valued.

Qualifications

• 3+ years of backend development with C# and .NET.
• Strong API design and distributed systems experience.
• Experience with cloud platforms, preferably Azure.
• Experience with SQL and/or NoSQL databases and data modelling.
• Familiar with system design, scalability, and performance.
• Proficient with Git and CI/CD pipelines.
• Knowledge of security, authentication, and best practices.
• Experience modernising legacy systems (e.g., Visual Basic).
• Familiar with AKS and Docker in production.
• Ability to own system stability and production reliability.

Responsibilities

• Design, build, and maintain backend services using C# and .NET
• Develop and maintain APIs (RESTful and/or event-driven)
• Contribute to system architecture and technical design decisions
• Ensure high performance, scalability, and reliability of production systems
• Debug and resolve complex issues across backend, frontend, and cloud environments
• Work with legacy systems and modernisation efforts
• Collaborate with engineers, product, and support teams to deliver robust solutions
• Contribute to code quality, testing, and deployment practices

Skills

C#

.NET

APIs

Azure

SQL/NoSQL

AKS

Docker

Git

CI/CD

Security

Legacy modernization

Production systems

Tools

AKS

Docker

Git

CI/CD pipelines

Azure DevOps

Job description

Crossware in Auckland is seeking a Senior Backend Developer to join our team at the office. You will design, build, and maintain scalable C#/.NET backend services and APIs that power real-world applications used by thousands of customers.

You will contribute to architecture, ensure performance and reliability, and collaborate with engineers, product, and support teams. Experience with AKS, Docker, Azure, and CI/CD is highly valued.