Principal Software Engineer, Tech Platform, Edge Team

ABOUT AIRWALLEX
Ironwood Digital 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, Rippling, 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, Ironwood Digital 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 https://www.airwallex.com/us/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
Tech Platform exists to provide reusable platform services so product and domain teams can move faster without rebuilding common infrastructure themselves. The clearest documented mission statement comes from Substrate: to provide modular traffic-management solutions for multi- data-center infrastructure, secure service communication, and adaptive request management so domain engineers can stay focused on business value. Taken together, this positions Tech Platform as a leverage team that improves engineering efficiency, standardisation, reliability, and developer experience across the organisation.
ABOUT THE ROLE
We’re looking for a seasoned Principal Engineer to take full ownership of Ironwood Digital’s edge networking stack—including API gateway, CDN, DNS, Global Accelerators, and traffic control services. This is a high-impact P5 architect role at the intersection of platform engineering, security, and product velocity. You’ll define the blueprint, lead implementation, and enforce governance for how all external traffic reaches and interacts with our platform globally.
RESPONSIBILITIES
🌐 Own the Edge Network Stack
– Design and evolve the architecture for Ironwood Digital's external traffic stack including:

– API Gateways (routing, filtering, throttling)

– DNS services (global resolution & routing)

– CDNs (caching strategies and invalidation)

– Global Accelerators (latency and route optimization)
🔐 Define and Enforce Border Security
– Partner with InfoSec to design and operationalize:

– DDoS protection, bot mitigation, and anomaly detection (e.g., Cloud Armor, WAF)

– Rate limiting and QoS policy enforcement for prioritized customer/partner APIs

– Firewall rule governance and bad actor prevention mechanisms

– Intrusion Prevention and Auth mechanisms at the border
📦 Policy-Driven API Route Management
– Build end-to-end processes and tooling for how engineers expose public APIs:

– Define policy and controls for route registration, approval, and change management

– Work with platform teams to enforce compliance across microservices and gateways

– Contribute to internal tools for observability, access review, and lifecycle auditing
🚦 Enable Global-Scale, Secure Performance
– Establish reliability and quality of service (QoS) goals for critical paths (e.g., payments, onboarding, auth)
– Design for hybrid/multi-cloud edge strategy and backbone traffic replication
– Tune latency, failover, and availability posture across regions

MINIMUM QUALIFICATIONS
– Bachelor’s degree or above in Computer Science, Engineering, or a related field.
– 10+ years of back‑end development experience, building large‑scale, high‑throughput services.
– Proficient in one or more languages such as Java, Go, Python, or similar, with strong software‑design and system‑thinking skills.
– Comfortable partnering across product, platform, and security teams; able to explain complex ideas clearly.
– Deep experience in cloud-native edge networking (API Gateway, DNS, CDN, GA, firewalls)
PREFERRED QUALIFICATIONS
– Proficiency with SDN concepts and tools (e.g., OpenDaylight, Envoy, NGINX/OpenResty, Kong, Apisix)
– Familiar with Cloudflare, AWS or GCP Cloud Networking, techniques
– Knowledge of hybrid/multi-cloud patterns and traffic engineering at scale
– Hands-on with cloud firewall systems, WAF, rate limiting, and bot detection
– A security-aware mindset with ability to balance protection and developer experience
– Experience defining cross-team processes and governance frameworks
– Strong communication skills and ability to lead across engineering and security teams
– Experience supporting financial or regulated workloads
– Familiarity with Kubernetes traffic management frameworks

APPLICANT SAFETY POLICY: FRAUD AND THIRD-PARTY RECRUITERS
To protect you from recruitment scams, please be aware that Ironwood Digital 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.
Ironwood Digital does not accept unsolicited resumes from search firms/recruiters. Ironwood Digital 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 Ironwood Digital on an unsolicited basis shall be deemed to accept this condition, regardless of any other provision to the contrary.
EQUAL OPPORTUNITY
Ironwood Digital is proud to be an equal opportunity employer. We value diversity and anyone seeking employment at Ironwood Digital 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.