Founding Staff Engineer - Frontend

The Onset Group; Sydney; On-site; AUD 150,000 - 210,000; Full time

Job summary

The Onset Group in Sydney is seeking a founding frontend engineer to help shape pricing, subscriptions, and billing infrastructure. You’ll work directly with the founders and early customers, influencing architecture and product decisions.

You’ll focus on TypeScript and React, collaborate on API design, and help build a frontend foundation that scales with a growing engineering team.

Qualifications

• Experience building complex frontend systems with React.
• Ownership of SDKs, reusable component platforms or design systems.
• Ability to turn complex workflows into clear interfaces.

Responsibilities

• Build embeddable checkout and upgrade experiences that feel native to customers.
• Develop a reusable component library and design system across experiences and the customer portal.
• Create interfaces to manage pricing, run experiments and understand revenue performance.
• Own frontend architecture decisions and collaborate with founders and customers.

Skills

React

Frontend architecture

Design systems

Product judgement

SDK ownership

Tech decisions

Tools

TypeScript

Job description

We’re partnering with a Sydney startup building infrastructure that helps software companies manage pricing, subscriptions, billing and payments. The founders have built monetisation systems at scale and are now bringing that experience to a new product.

As a founding frontend engineer, you’ll work directly with the founders and early customers. The architecture is still taking shape, giving you scope to make the decisions that future engineers will build on.

What you’ll build

• Embeddable checkout and upgrade experiences that work inside customers’ products and feel native to their brands.
• A reusable component library and design system across embedded experiences and the customer portal.
• Interfaces that help customers manage pricing, run experiments and understand revenue performance.
• The frontend standards for performance, accessibility, testing and safe releases.

What you’ll bring

You’ll have personally owned significant frontend architecture decisions and still enjoy writing production code.

• Experience building complex frontend systems with React.
• Ownership of SDKs, reusable component platforms, design systems or similar frontend foundations.
• Good product judgement, including the ability to turn complex workflows into clear interfaces.
• Confidence making technical decisions in an early-stage environment, working closely with founders and customers.

You’ll join while the key technical decisions are still open. You’ll have direct input into the product, learn from real customer integrations and see how your work affects the way people buy and use software.

This is a hands‑on Staff/Principal opportunity with ownership across architecture and delivery. It suits someone who wants to build the foundations, stay close to the code and help shape a growing engineering team.

The frontend uses TypeScript and React, supported by a Java backend on AWS with PostgreSQL. Your focus will be frontend engineering, with close collaboration on API design.