Senior Fullstack Engineer, Scale

ABOUT AIRWALLEX Airwallex is the AI-native financial operating system for a real-time, intelligent economy. More than 675,000 businesses, including McLaren Racing, Qantas, SHEIN, and TikTok, use us, directly or through our platform partners, to run their financial operations or build and monetize financial products of their own. We started in Melbourne in 2015 to build the infrastructure global commerce runs on. We're the regulated backbone behind global payments: not by accident, but by design. A decade plus, 85+ licenses, and a financial infrastructure spanning North America, Europe, the Middle East, and Asia-Pacific. We're co-headquartered in San Francisco and Singapore, with more than 2,700 people across 27 offices. We hire builders with founder-level energy, people who move fast with good judgment, dig in with real curiosity, and make calls from first principles rather than waiting to be told what to do. Read our operating principles https://www.airwallex.com/en-us/operating-principles to see it in full. HOW YOU'LL MAKE IMPACT Own the frontend work for the Scale team, taking responsibility for the design, implementation, and ongoing quality of user-facing experiences across our platform products. You'll work independently on ambiguous problems, partnering with backend engineers, Product, Design, and other stakeholders to turn customer and business requirements into reliable, maintainable solutions. - Build and maintain frontend experiences across the stack, with particular ownership and depth in React-based development - Deliver reliable, maintainable solutions for multi-tenant platforms, enterprise integrations, and cross-domain product features - Partner with backend engineers, Product, Design, and other stakeholders to turn customer and business requirements into effective technical solutions - Make pragmatic decisions in ambiguous situations, balancing flexibility, simplicity, and maintainability in system and component design You'll work from our London office three days a week. ESSENTIALS - Strong experience building frontend applications with ReactJS. - Experience with modern JavaScript or TypeScript. - Experience working across the full stack, with the ability to own frontend work end to end. - A track record of working independently and delivering high-quality software with minimal oversight. - The ability to make pragmatic technical decisions in ambiguous situations. - Clear communication across technical and non-technical stakeholders. - Make pragmatic decisions on when to optimize for performance vs. velocity based on business impact - Thrive in cross-functional environments spanning Product, Design, Compliance, and Sales - Design for scale, maintainability, and production excellence PREFERRED - Fintech, payments, or regulated industry experience. - High-scale performance tuning (100k+ QPS, large user bases, strict latency SLAs). - Multi-tenant SaaS or platform architecture background. - Proficiency with PostgreSQL, Redis, Kafka, or cloud platforms (AWS/GCP/Azure). - Experience with OAuth2.0, API design, or developer documentation. - Cross-region deployment or data residency compliance experience. - Solutions engineering or customer-facing technical experience. LEARN MORE ABOUT YOUR TEAM The Scale team builds the infrastructure that lets platforms embed Airwallex financial products at speed and with confidence. The team owns multi-tenant systems powering companies like Brex, Rippling, Navan, Qantas, and SHEIN. The engineering challenges are real: balancing tenant isolation with resource efficiency, low-latency performance with cross-data-center resilience, and immediate customer needs with long-term architectural extensibility. Beyond infrastructure, the team owns cross-domain product features and designs enterprise integrations by translating customer business requirements into scalable technical solutions. APPLICANT SAFETY POLICY: FRAUD AND THIRD-PARTY RECRUITERS To protect you from recruitment scams, please be aware that Airwallex will not ask for bank details, sensitive ID numbers (i.e. passport), or any form of payment during the application or interview process. All official communication will come from an @airwallex.com http://airwallex.com email address. Please apply only through careers.airwallex.com http://careers.airwallex.com or our official LinkedIn page. Airwallex does not accept unsolicited resumes from search firms/recruiters. Airwallex will not pay any fees to search firms/recruiters if a candidate is submitted by a search firm/recruiter unless an agreement has been entered into with respect to specific open position(s). Search firms/recruiters submitting resumes to Airwallex on an unsolicited basis shall be deemed to accept this condition, regardless of any other provision to the contrary. EQUAL OPPORTUNITY Airwallex is proud to be an equal opportunity employer. We value diversity and anyone seeking employment at Airwallex is considered based on merit, qualifications, competence and talent. We don’t regard color, religion, race, national origin, sexual orientation, ancestry, citizenship, sex, marital or family status, disability, gender, or any other legally protected status when making our hiring decisions. If you have a disability or special need that requires accommodation, please let us know.