Staff Software Engineer - Full Stack -.NET, API

Location: Sydney CBD Area, Melbourne, VIC - 357 Collins Street

Time Type: Full time

Job Description

• We're embarking on an engineering transformation with a key focus across full stack full cycle experience including: .NET, AWS and AI powered services.

• You have knowledge that spans both development and operations, including coding, infrastructure management, system admin/engineering, and DevSecOps Toolchains. 

• Together we will build tomorrow’s bank today, using world-leading engineering, technology, and innovation.

Do work that matters:

We're building tomorrow’s bank today, which means we need creative and diverse engineers to help us redefine what customers expect from a bank. Envisioning new technologies that are still waiting to be invented and reimagining products that support our customers and help build Australia’s future economy.

The Customer Onboarding & Lifecycle Crew is where work truly matters, owning the end-to-end journey that every business customer depends on to get started. This is high-impact, high-complexity engineering at its core, shaping how businesses enter and interact with the bank from day one. As a Staff Software Engineer, you don’t just contribute, you lead from the front with full-cycle ownership: investigating problems, designing solutions, building, testing, running, and continuously improving critical platforms.

Grounded in .NET backend engineering with a full-stack mindset, you operate at scale while driving strategic direction, uplifting engineering standards, and mentoring those around you. This is a team pushing boundaries, leveraging cutting-edge cloud services, evolving ways of working, and harnessing AI-powered agents and platforms to simplify complexity and accelerate outcomes. The impact is real, immediate, and far-reaching, what you build here sets the foundation for every business customer’s journey and enables the entire ecosystem to move faster with confidence.

See yourself in our team:  

The CBA technology unit delivers the best digital banking services to Commonwealth Bank customers and to do so is responsible for digital delivery, group data and analytics, technology and technology infrastructure, cyber, fraud, physical security and business resilience for all divisions across CBA. It is also dedicated to delivering the best workplace technology experience for our over 53.000 people across CBA and focused on providing the latest tools, technology, and resources to enhance the way we work together and empower our people to achieve more for our customers.

The Customer Onboarding & Lifecycle crew sits at the heart of the Business Banking Technology domain, owning the critical first mile of every business customer’s journey. Their work directly shapes how quickly, safely, and confidently customers can start doing business, balancing seamless digital experiences with rigorous compliance. Behind the scenes, they engineer robust .NET Core backend platforms, scalable APIs, and cloud-native AWS solutions, while pushing forward with AI-driven, agentic capabilities to reduce friction and intelligently handle complexity.

As the entry point for the entire ecosystem, every downstream crew depends on the quality, reliability, and intelligence of what this team delivers making their impact both immediate and far-reaching. What they do matters because it sets the tone for trust, unlocks growth for businesses, and underpins the bank’s ability to operate at scale with confidence.

We’re interested in hearing from people who: 

• Act as a technical SME and engineering leader, shaping long-term architecture and platform strategy while remaining deeply hands-on in building scalable, cloud-native solutions using .NET/.NET Core, C#, and AWS

• Design, build, and optimise backend systems (APIs, microservices, data access layers, event-driven services) with a strong focus on performance, resilience, and clean architecture patterns

• Drive end-to-end solution delivery across the full stack, with primary depth in backend engineering and sufficient front-end capability (React, Next.js, TypeScript) to deliver cohesive user experiences

• Lead platform architecture evolution, influencing microservices design, event-driven integrations, and cloud-native deployment patterns while setting engineering standards and best practices

• Champion high-quality engineering through CI/CD (GitHub Actions, Artifactory), automated testing (TDD/BDD), observability (CloudWatch, Grafana, Splunk), and DevSecOps practices

• Collaborate closely with stakeholders to translate business requirements into scalable technical solutions, contributing to design decisions and driving measurable business value

• Continuously innovate and improve engineering workflows through automation (Python, PowerShell), deep troubleshooting, and optimisation of cloud infrastructure and delivery pipelines

• Apply an AI-first engineering mindset, leveraging AI-assisted development tools, cloud AI services, and intelligent automation to accelerate delivery and enhance system capabilities

• Develop and scale AI-enabled solutions, including LLM integrations and emerging agent-based workflows, while mentoring engineers and uplifting team capability in modern engineering and AI practice. 

Tech skills 

We don't expect you to know everything, but experience in several of the following will set you up for success:

• Back-End Engineering (.NET Core Focus): C#, .NET, ASP.NET Core, Web API, Entity Framework Core, Dapper, SQL Server, PostgreSQL, gRPC, REST

• Front-End Engineering (Supporting Full-Stack Delivery): JavaScript, TypeScript, React, Next.js, HTML5, CSS3

• API Design & Integration: RESTful APIs, OpenAPI/Swagger, gRPC, API Versioning, Contract-First Design, OAuth 2.0, JWT, API Gateway, Rate Limiting

• Event-Driven Architecture: Kafka, AWS Kinesis, SNS/SQS, EventBridge, Pub/Sub Patterns, Asynchronous Messaging

• Cloud-Native Development (AWS): AWS (Lambda, ECS, EKS, API Gateway, DynamoDB, RDS, S3), Microservices Architecture, Service-to-Service Communication

• Containers & Orchestration: Docker, Kubernetes, Helm, Containerisation, Cluster Management

• DevSecOps & CI/CD: GitHub Actions

• Observability & Reliability (SRE): Prometheus, Grafana, AWS CloudWatch, Splunk, OpenTelemetry, Distributed Tracing, Logging, Metrics, Alerting

• Quality Engineering & Testing: TDD, BDD, xUnit, NUnit, Integration Testing, API Testing, Selenium, Test Automation Frameworks

• Performance & Load Testing: k6, JMeter, Gatling, Locust, BlazeMeter, LoadRunner

• Security Engineering: Secure Coding Practices, Authentication & Authorization, OWASP, Encryption, Threat Modeling

• AI & Agentic Systems Enablement: LangGraph, Strands SDK, LLM Integration, RAG, AI Prompt Engineering, Agentic Workflow Design

• Full Lifecycle Delivery: System Design, Development, Testing, Deployment, Monitoring, Continuous Improvement.