Senior Backend Engineer, Stablecoin Platform

Airwallex; Singapore; On-site; SGD 120,000 - 180,000; Full time

Job summary

Airwallex is seeking a senior engineer to lead the development of our stablecoin infrastructure and blockchain integration within a global payments platform. You will architect and build secure systems for key management, transaction signing, and cross-chain settlement, shaping the next generation of tokenised currency for our FX and payments stack.

You will collaborate with product, infra, and compliance teams to deliver auditable, production-grade services while ensuring safe handling of

Qualifications

• 5+ years as engineer with OO design and production-grade software.
• Experience building and integrating blockchain infrastructure into financial systems.
• Experience integrating new systems into legacy or distributed environments without instability.
• Strong knowledge of private key handling, signing, encryption, and operational controls.
• Clear communicator across engineering, product, and non-technical teams.

Responsibilities

• Be part of a high-impact engineering team building stablecoin infrastructure from the ground up.
• Design and implement secure systems for key management, transaction signing, gas fee management, and blockchain integration
• Own services that manage the full lifecycle of stablecoin transactions mint, burn, transfer, reconciliation
• Build internal ledgering systems that track balances across multiple chains and token types
• Integrate stablecoin infrastructure into Airwallex’s existing FX and payment systems, enabling seamless conversion between any supported currency and stablecoins
• Write, review, and ship production code
• Collaborate with product, infrastructure, and compliance teams to deliver reliable and auditable services

Skills

5+ years engineering experience

Object-oriented design

Strongly typed languages (Kotlin/Java/

Blockchain infrastructure experience

Secure system design

Cross-team collaboration

Tools

Kotlin

Java

C#

C++

Rust

Job description

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, 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, 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
The Financial Markets team is responsible for Airwallex’s core FX and liquidity infrastructure. We’re now expanding into building the stablecoin infrastructure that will enable both customers and internal systems to buy, hold, send, and settle with tokenised currency globally. This includes support for near‑instant global payments, on‑chain liquidity, and seamless conversion between fiat and stablecoin balances. We’re building stablecoins into the core of Airwallex’s infrastructure, so they function as seamlessly as any fiat currency across our global platform.

We're seeking a skilled developer to take a leading role in advancing our initiatives. Someone who can both architect and build robust, reliable systems and tackle the challenges of blockchain integration, digital asset custody, and global payments infrastructure.

What You’ll Do

• Be part of a high‑impact engineering team building stablecoin infrastructure from the ground up.
• Design and implement secure systems for key management, transaction signing, gas fee management, and blockchain integration
• Own services that manage the full lifecycle of stablecoin transactions mint, burn, transfer, reconciliation
• Build internal ledgering systems that track balances across multiple chains and token types
• Integrate stablecoin infrastructure into Airwallex’s existing FX and payment systems, enabling seamless conversion between any supported currency and stablecoins
• Write, review, and ship production code
• Collaborate with product, infrastructure, and compliance teams to deliver reliable and auditable services

Responsibilities

Minimum qualifications:

• A highly experienced engineer (5+ years) with deep expertise in object‑oriented design and production‑grade software development, including at least one strongly typed language (e.g. Kotlin, Java, C#, C++, Rust); Python experience is useful but not sufficient on its own
• Proven experience building and integrating blockchain infrastructure (wallets, transaction flows, key management, etc.) into larger financial systems
• Experienced in integrating new systems into legacy or distributed environments without introducing instability or regressions.
• Strong grasp of secure system design, particularly around private key handling, signing, encryption, and operational controls
• Able to quickly pick up unfamiliar tools or frameworks when needed and adjust to changing technical priorities.
• Clear communicator who works well across engineering, product, and non‑technical teams

Preferred qualifications:

Experience in FX, payments, or financial infrastructure is useful but not required

#Singapore

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.