Staff Software Engineer, Payments

About Airwallex Airwallex is the only unified payments and financial platform for global businesses. Powered by our unique combination of proprietary infrastructure and software, we empower over 250,000 businesses worldwide – including Brex, Navan, Qantas, SHEIN and many more – with fully integrated solutions to manage everything from business accounts, payments, spend management and treasury, to embedded finance at a global scale. Proudly founded in Melbourne, we have a team of over 2,300 of the brightest and most innovative people in tech across 27 offices around the globe. Valued at US$11 billion and backed by world-leading investors including T. Rowe Price, Visa, Mastercard, Robinhood Ventures, Sequoia, Salesforce Ventures, DST Global, and Lone Pine Capital, Airwallex is leading the charge in building the global payments and financial platform of the future. If you’re ready to do the most ambitious work of your career, join us. Attributes We Value We hire successful builders with founder-like energy who want real impact, accelerated learning, and true ownership. You bring strong role-related expertise and sharp thinking, and you’re motivated by our mission and operating principles . You move fast with good judgment, dig deep with curiosity, and make decisions from first principles, balancing speed and rigor. You're humble and collaborative; turn zero‑to‑one ideas into real products, and you “get stuff done” end-to-end. You use AI to work smarter and solve problems faster. Here, you’ll tackle complex, high‑visibility problems with exceptional teammates and grow your career as we build the future of global banking. If that sounds like you, let’s build what’s next. About the team In our Payments Team, your responsibilities extend beyond delivering product features to achieving business outcomes. Your tasks will involve developing various REST services and integration components within a backend microservices architecture, connecting with our React frontend. We’re looking for a Staff Software Engineer to help define the technical direction of our Payments platform, lead complex architecture decisions, and build highly reliable, high-volume distributed systems that directly impact merchant experience and business outcomes. What You’ll Do Lead the architecture and evolution of next-generation Payment Acceptance infrastructure. Design and build scalable backend services, REST APIs, event-driven systems, and integration components within a microservices architecture. Drive complex initiatives across payment gateways, acquiring, issuing, card networks, and local payment methods. Partner with product, business, infrastructure, and external engineering teams to translate merchant needs into technical solutions. Conduct architectural reviews, address technical debt, and improve system reliability, scalability, and operational effectiveness. Raise the engineering bar through strong design practices, code quality, testing, observability, and mentorship. Minimum Qualifications 10+ years of software engineering experience, including Staff-level technical leadership or equivalent ownership of complex backend systems. Strong experience designing and operating high-volume distributed systems, preferably in payments, fintech, commerce, or financial infrastructure. Recent hands-on experience with Java or Kotlin and Spring / Spring Boot. Expertise building REST APIs, backend microservices, Kafka-based event streams, and distributed data stores such as Cassandra, Hazelcast, Oracle Coherence, or similar. Experience with cloud platforms such as GCP or AWS, plus Docker and Kubernetes. Strong familiarity with observability and operational tooling such as New Relic, StatsD, ELK, Datadog, Prometheus, or similar. Proven ability to lead projects from concept to production with a focus on quality, testing, reliability, and maintainability. Excellent communication skills and ability to influence across engineering, product, and business stakeholders. Preferred Qualifications Experience building payment gateways, acquiring platforms, issuing platforms, or payment acceptance infrastructure. Experience integrating major card networks such as Visa and Mastercard. Experience with local payment methods such as iDEAL, Klarna, Trustly, or similar. Familiarity with authorization, capture, refunds, chargebacks, settlement, reconciliation, fraud, risk, or PCI/compliance workflows. Experience mentoring senior engineers and leading cross-team technical initiatives. 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 email address. Please apply only through 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.