Senior Software Engineer (Backend)

About Boku

Boku is a global provider of local mobile-first payments solutions. Its payment network supports more than 250 local payment methods across 65 countries.

The role

As a Senior Backend Software Engineer, you will join a small, autonomous team in Singapore building a new suite of products from the ground up. You will design and deliver production-grade services for payment initiation, payouts, card processing, foreign exchange, reconciliation and settlement. The work is focused on new product development, with reliability and observability built in from the start.

What you will do

• Design and build high-throughput, low-latency, highly available services using Java and Spring Boot.

• Develop REST, gRPC and event-driven APIs for payment initiation, callbacks, reconciliation and settlement.

• Build resilient services using idempotency, retries, circuit breakers and graceful degradation.

• Develop new payout processing, card processing, FX, treasury orchestration and cash forecasting capabilities.

• Design data access and storage using relational and NoSQL databases; profile and improve service performance.

• Contribute to secure system design, including PCI DSS requirements, access controls and audit logging.

• Build observability into services through structured logs, distributed tracing, metrics and alerting; contribute to service objectives.

• Establish delivery foundations including CI/CD, Docker and EKS configuration, and code quality and security checks.

• Review code and work with product, design, architecture, security and globally distributed engineering colleagues.

• Contribute React components for internal tools, operational dashboards or merchant-facing interfaces when needed.

• Where relevant, integrate FX data sources and support treasury and cash-position monitoring.

• Explore production use of LLM-powered features and agent workflows, with suitable controls, retries and human review.

What you bring

• At least 5 years of backend software engineering experience, with strong Java and Spring Boot skills.

• Experience building distributed, high-throughput and highly available payment or financial services.

• Understanding of payment architecture, including idempotency, delivery guarantees, reconciliation and settlement.

• Experience with relational databases such as PostgreSQL or MySQL and messaging systems such as Kafka or RabbitMQ.

• Familiarity with Docker, Kubernetes or EKS and CI/CD tooling.

• Knowledge of secure coding and PCI DSS-aligned system design.

• A bachelor's degree in Computer Science, Engineering or equivalent practical experience.

• Strong communication skills and the ability to collaborate across product and engineering teams.

Additional experience that would be useful

• React development for internal tools or dashboards.

• FX data feeds such as Bloomberg, FX or treasury systems, multi-currency settlement, or ISO 20022 and SWIFT messaging.

• Work at a payments processor, payment service provider or fintech serving multiple markets.

• Building or integrating LLM-powered services, using tool calling and structured outputs, or AWS Bedrock.

• Agentic workflows or MCP (Model Context Protocol), and experience using AI-assisted development tools with sound engineering judgement.

Why join Boku

Help build payment infrastructure for global digital commerce in a collaborative, international engineering environment, working on new products with colleagues across markets.