Team Lead - Core Web

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

Job summary

The Onset in Sydney seeks an experienced Frontend Engineering Lead who remains hands-on while guiding a small team of frontend engineers. You will shape frontend architecture, improve performance and set engineering standards across high-traffic customer-facing products.

You will design and build modern frontend applications in React and TypeScript, mentor engineers, and drive pragmatic technical decisions as the platform evolves.

Qualifications

• Strong commercial experience with React and TypeScript and modern JavaScript.
• Experience designing and building large or complex frontend applications.
• Deep understanding of frontend architecture and system design.
• Experience with micro-frontends and monorepo environments.
• Experience improving frontend performance and Core Web Vitals.
• Ability to mentor engineers and lead technical decision-making.

Responsibilities

• Design and build modern frontend applications using React and TypeScript.
• Make architectural decisions across complex frontend systems.
• Mentor and lead a small team of frontend engineers.
• Review code and maintain high engineering standards.
• Collaborate with Product, Design, Backend, QA and other teams.
• Balance technical quality with delivery timelines.

Skills

React

TypeScript

JavaScript

Frontend architecture

Micro-frontends

Monorepos

Tools

CI/CD

Automated testing

Frontend tooling

Observability

Web performance tooling

Job description

Frontend Engineering Lead

We’re looking for an experienced Frontend Engineering Lead to join a large-scale digital product environment.

This is a hands-on engineering role for someone who still wants to spend the majority of their time close to the technology, while also providing technical direction and supporting a small team of engineers.

You’ll work across high-traffic customer-facing products, helping shape frontend architecture, improve performance and engineering standards, and make practical technical decisions as the platform continues to evolve.

The role is approximately 60% hands-on engineering and 40% technical and team leadership.

What You’ll Be Doing

• Design and build modern frontend applications using React and TypeScript
• Make architectural decisions across complex frontend systems
• Work with micro-frontends, monorepos and shared frontend platforms
• Break down larger technical problems into practical engineering solutions
• Improve application performance, reliability and maintainability
• Identify and address frontend performance issues, including Core Web Vitals
• Review code and help maintain high engineering standards
• Guide engineers through technical decisions and complex problems
• Mentor and support a small team of frontend engineers
• Work closely with Product, Design, Backend, QA and other engineering teams
• Contribute to system design discussions and longer-term technical direction
• Balance technical quality with delivery timelines and business priorities
• Help improve testing, observability and engineering practices across the team

You’ll need strong hands-on frontend engineering experience and enough technical depth to lead engineering decisions rather than simply manage delivery.

Ideally, you’ll bring:

• Strong commercial experience with React and TypeScript and modern JavaScript
• Experience designing and building large or complex frontend applications
• Strong understanding of frontend architecture and system design
• Experience with micro-frontends and/or monorepo environments
• Experience improving frontend performance and Core Web Vitals
• Good understanding of rendering, browser performance and application behaviour
• Experience with automated testing and modern frontend engineering practices
• Experience working with APIs and distributed backend systems
• Strong code review and technical problem-solving skills
• Experience mentoring or technically leading other engineers
• Ability to explain technical decisions, trade-offs and alternative approaches clearly
• Experience working in cross-functional product and engineering teams

You’ll remain hands-on while helping a small engineering team perform at a high level.

That could include:

• Supporting engineers with technical problems
• Providing feedback through code and design reviews
• Mentoring engineers and helping develop their capability
• Setting technical standards
• Helping resolve disagreements around technical direction
• Working with individuals when performance or delivery issues arise
• Creating an environment where engineers can make good decisions independently

Experience across some of the following would be useful:

• React
• TypeScript / JavaScript
• Micro-frontends
• Monorepos
• Modern frontend build tooling
• Automated testing
• CI/CD
• Observability and monitoring
• Web performance
• Core Web Vitals
• APIs and distributed systems
• Cloud-based production environments

You don’t need to have used every technology listed, but you should have worked on complex production frontend systems where performance, scale and maintainability matter.

You’ll suit this role if you’re comfortable moving between writing code, reviewing architecture, helping another engineer solve a problem and discussing technical trade-offs with stakeholders.

You should be able to go deeper than simply describing what technology you used. We’re looking for someone who can explain why decisions were made, what alternatives were considered, what could fail and how the system behaves at scale.

Location: Sydney

This role includes regular office-based collaboration, with the team currently workingfour days per week.