Senior Frontend Lead: React/TypeScript for Scalable Systems

The Onset; Sydney; On-site; AUD 180,000 - 260,000; Full time

Job summary

The Onset is seeking a Staff Frontend Engineer to join a large-scale digital product environment. You will own complex frontend and architecture challenges, remaining hands-on while guiding engineers through technical design decisions and performance improvements.

You will influence technical direction across high-traffic customer-facing products, mentor peers, and partner with product, design, and architecture teams to ensure scalable, reliable solutions.

Qualifications

• Proven experience with React and TypeScript in large-scale frontend environments.
• Strong frontend architecture and system design capabilities.
• Experience at Staff, Principal, Lead, or senior technical leadership level.
• Proven ability to operate across high-traffic customer-facing platforms.
• Solid understanding of frontend performance and scalability.
• Experience with APIs, distributed systems, and backend services.
• Strong knowledge of testing, CI/CD, observability, and production support.
• Ability to clearly explain trade-offs and guide engineering decisions.
• Experience mentoring engineers and influencing technical direction.

Responsibilities

• Design and evolve frontend architecture across large-scale web applications.
• Remain hands-on with React, TypeScript, and modern JavaScript.
• Lead system design and drive technical decision-making.
• Improve performance, reliability, scalability, and maintainability.
• Review code and uplift engineering standards.
• Collaborate across frontend, backend, and platform teams.
• Mentor engineers and support solving complex technical problems.
• Partner with product, design, and architecture on solution direction.
• Identify technical risks and opportunities for improvement.
• Help teams make pragmatic architecture and delivery decisions.

Skills

React

TypeScript

Frontend architecture

Leadership

High-traffic systems

Performance optimization

APIs & distributed systems

Testing & CI/CD

Observability & production support

Job description

The Onset is seeking a Staff Frontend Engineer to join a large-scale digital product environment. You will own complex frontend and architecture challenges, remaining hands-on while guiding engineers through technical design decisions and performance improvements.

You will influence technical direction across high-traffic customer-facing products, mentor peers, and partner with product, design, and architecture teams to ensure scalable, reliable solutions.