(Senior) Software Engineer, Payments Team - API & Checkout Experience

Airwallex5 months ago

Location

SG - Singapore

Type

Full Time

Level

Senior

Role

Backend Engineer

Posted

Sep 22, 2025

Full TimeSenior

The role

Summary

Senior Software Engineer role on Airwallex's Payments Team focusing on API & Checkout Experience development. Based in Singapore, you'll design and maintain payment APIs, SDKs, and checkout features for global merchants while working with distributed systems and real-time transaction processing. The role requires 3-5+ years of experience with strong Kotlin/Java skills and system design expertise.

What you'll do

API Development: Design, develop, and maintain APIs and Checkout features for various payment scenarios including front-end SDKs, mobile SDKs, and Payment Link products

Global Infrastructure: Collaborate with various systems and teams to establish robust foundation for global payment infrastructure

Cross-Team Collaboration: Engage with engineering teams across Airwallex's global offices (China, Netherlands, Singapore) fostering effective communication

Partner Integration: Regularly collaborate with users and financial partners to ensure seamless integration and payment processing

System Maintenance: Design, develop, and maintain services and systems to uphold reliable payment processing flow with high availability

Production Support: Troubleshoot production issues across different levels of the technology stack

Performance Optimization: Take ownership of and optimize critical components within Airwallex's online payment processing flow

Feature Development: Actively develop new payment features and optimize existing codebase for scalability and performance

What we look for

Technical

Backend DevelopmentMinimum 3-5+ years of software engineering experience with focus on backend systems

System DesignStrong aptitude for system thinking and designing elegant systems that abstract complex patterns, particularly in financial industry

Code QualityDemonstrated ability to write high-quality, maintainable code and documentation

Production SystemsExperience maintaining high standards when working with production systems

Engineering Best PracticesAdherence to best practices in engineering, security, and design

Programming LanguagesProficiency in Kotlin (preferred) or Java and other modern programming languages

API DevelopmentStrong understanding of HTTP protocol and RESTful API specifications

Education

Computer Science DegreeBachelor's degree in Computer Science, Software Engineering, or related technical field preferred

Experience

Software Engineering3+ years for mid-level, 5+ years for senior-level engineering experience

Financial TechnologyExperience in fintech or payments industry preferred but not required

Distributed SystemsExperience with large-scale distributed systems and real-time transaction processing

API DesignExperience designing, implementing, and maintaining complex public API products with user integration guides

Skills

Required skills

Kotlin/JavaStrong proficiency in Kotlin (preferred) or Java programming

System DesignAbility to design elegant systems and abstract complex patterns

REST APIsDeep understanding of HTTP protocol and RESTful specifications

Production SystemsExperience maintaining high-availability production systems

CollaborationStrong collaborative skills for working with diverse stakeholders

Code QualityHigh standards for code quality, documentation, and engineering practices

Nice to have

Spring Boot/FrameworkExperience with Spring ecosystem for Java development

Database TechnologiesProficiency with PostgreSQL, Redis, and NoSQL databases

Message QueuesExperience with Kafka, RabbitMQ for asynchronous processing

AuthenticationFamiliarity with OAuth2.0, JWT for secure API access

InfrastructureExperience with Nginx, Istio service mesh

Cloud PlatformsExperience with AWS, GCP, or Alibaba Cloud

API Product DesignExperience designing complex public API products with integration guides

English CommunicationFluent English communication for global team collaboration

Compensation & benefits

Benefits

Global Work Environment

Work with diverse team across 26 offices globally including China, Netherlands, and Singapore

Career Growth

Accelerated learning opportunities and true ownership in a rapidly growing fintech unicorn

Innovation Focus

Work on cutting-edge payment technology and explore AI applications in business scenarios

Relocation Support

Relocation assistance available from Shanghai to Singapore

Equal Opportunity

Equal opportunity employer with strong commitment to diversity and inclusion

Interview process

1
Application Review — Initial screening of resume and application materials
2
Technical Phone Screen — Phone or video call to assess technical background and coding skills
3
Technical Interviews — Multiple rounds focusing on system design, coding, and API development experience
4
Cross-Team Interviews — Interviews with various stakeholders to assess collaboration and communication skills
5
Final Interview — Final round with senior leadership to discuss role fit and career goals