Senior Backend Engineer, Billing Platform (Java)

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

Job summary

Airwallex in Singapore is seeking a senior Backend Engineer to lead design and implementation of backend systems for our billing platform. You will collaborate with Product and business teams to translate requirements into scalable solutions and own critical components in a microservices architecture.

With 6+ years of Java development and a track record delivering large-scale financial systems, you will ensure high concurrency, reliability, and financial accuracy across global billing workflows.

Qualifications

• 6+ years of core Java development experience and 5+ years building large-scale financial or ecommerce platforms.
• Bachelor's degree in Computer Science or related field.
• Strong command of Java 8, including multithreading, high concurrency, I/O/NIO, and network communication.
• Experience designing and developing large-scale distributed, high-concurrency, high-load systems.
• Experience with server-side technologies and optimizing queries for performance.
• Proven ability to solve complex engineering problems in production environments.
• Ability to collaborate with Product and business teams to translate needs into technical solutions.

Responsibilities

• Lead the planning, design, and implementation of backend systems for Airwallex’s billing platform.
• Partner with Product and business teams to understand needs, shape technical direction, and deliver core functionality.
• Build reliable components within a microservices architecture for pricing, invoicing, and quote-to-cash workflows.
• Own the architecture and development of complex distributed systems with high concurrency and financial accuracy.
• Introduce practical technologies and engineering practices to improve how the team builds, operates, and scales billing products.
• Raise the bar on engineering quality through clear design practices and coding standards.

Skills

Java development

High concurrency

Backend architecture

Cross-functional

Education

Bachelor's in Computer Science

Job description

Airwallex in Singapore is seeking a senior Backend Engineer to lead design and implementation of backend systems for our billing platform. You will collaborate with Product and business teams to translate requirements into scalable solutions and own critical components in a microservices architecture.

With 6+ years of Java development and a track record delivering large-scale financial systems, you will ensure high concurrency, reliability, and financial accuracy across global billing workflows.