Senior Frontend Engineer - Core Web, React/Next.js

CoStar Group, Inc.

Sydney

On-site

AUD 140,000 - 190,000

Full time

3 days ago

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Job summary

CoStar Group, Inc. is seeking an Senior Engineer (Core Web) in Sydney to drive high-quality software development and architectural decisions.

You will lead the frontend stack with React, TypeScript, and Next.js, building scalable, high-traffic web applications while mentoring junior engineers and aligning with product goals. You will optimise Core Web Vitals, collaborate with product and design teams, and contribute to platform reliability and security.

Qualifications

Degree in Computer Science, Software Engineering, or a related discipline.
Strong expertise in modern frontend technologies, including React, JavaScript, TypeScript, and Next.js.
Experience building scalable, high-traffic web applications using modern architectural patterns such as Micro Frontends, SPA, and SSR.
Experience working with GraphQL, cloud-native technologies (AWS), containerisation (Docker), and modern CI/CD practices.
Proficiency in designing and delivering high-quality software solutions within Agile development environments.
Collaborative mindset with proven experience working across Product, Design, and Engineering teams to deliver customer-focused outcomes.
Demonstrated ability to mentor junior engineers, contribute to engineering best practices, and drive continuous improvement within development teams.
Security: Familiarity with modern Application Security Practices (OWASP) preferred.
Deep understanding of web performance optimisation, including Core Web Vitals (INP, LCP, CLS, and TTFB).

Responsibilities

Build high-quality, scalable, and reliable solutions, applying modern engineering best practices and contributing to continuous improvement across the technology landscape.
Demonstrate strong expertise in web performance optimisation, including Core Web Vitals (LCP, INP, CLS, and TTFB), with a focus on delivering exceptional customer experiences.
Contribute to the health, stability, and evolution of platforms by addressing technical debt, improving system performance, and influencing engineering standards through collaboration with broader technical communities.
Mentor and support junior engineers, while partnering closely with Product Managers and Designers to deliver customer-centric outcomes aligned with business goals.
Take ownership of operational excellence, including participating in on-call rotations, responding to incidents, and proactively improving system reliability, security, and maintainability.