Senior Software Engineer | Full Stack .NET & React

Big Wave Digital; Sydney; On-site; AUD 140,000 - 190,000; Full time

Job summary

Big Wave Digital is seeking a Senior Software Engineer to join the customer acquisition team for a financial services client. You’ll own features from design through release, building in React/TypeScript with .NET APIs and services.

You’ll shape technical decisions and impact onboarding, identity and promotions, while collaborating with design, product and compliance teams. The role emphasizes hands-on ownership across the stack, with a focus on conversion, performance and accessibility to

Qualifications

• Strong full-stack engineering experience with solid .NET skills and frontend product experience.
• Excellent understanding of React and TypeScript frontends with robust API integration.
• Experience with relational databases and data-driven rules.
• Experience with building maintainable, testable code and edge cases.
• Curiosity about how technical decisions affect customer experience and conversion.

Responsibilities

• Build customer-facing features in React and TypeScript and APIs/services in .NET.
• Improve onboarding, SSO and systems determining customer information requirements.
• Own features from design discussions through release and ongoing improvement.
• Work closely with design, product, compliance and other engineers.
• Maintain performance, reliability, accessibility and maintainability.

Skills

React

TypeScript

.NET

Full-stack

Frontend development

APIs

Performance

Ownership

Tools

Relational databases

Headless CMS

OAuth/OIDC or SAML

Job description

Build the first experience customers have with a financial platform.

We’re recruiting a Senior Software Engineer for a financial services client’s customer acquisition team. You’ll work on the journey from someone’s first visit to becoming an active customer: the public website, onboarding, identity verification, sign-in and promotions.

This is a hands‑on role with real ownership. You’ll build across the stack, help shape technical decisions and see how your work affects customer experience and growth.

What you’ll do

• Build customer-facing features in React and TypeScript, alongside APIs and services in .NET.
• Improve onboarding, SSO and the systems that determine what information each customer needs to provide.
• Own features from design discussions through release and ongoing improvement.
• Work closely with design, product, compliance and other engineers.
• Keep performance, reliability, accessibility and maintainability front of mind.

What you’ll bring

• Strong full-stack engineering experience, with solid .NET skills and confidence building frontend products in React and TypeScript.
• Experience with relational databases, data-driven rules and headless CMS platforms.
• An eye for edge cases and a habit of writing clear, testable code.
• Curiosity about how technical decisions affect conversion and the customer experience.
• The confidence to take ownership while priorities evolve.

Experience with OAuth/OIDC or SAML, KYC integrations, multilingual websites, technical SEO or high-conversion digital products would be a bonus.