Backend Engineer, Card Issuing

Location: Kuala Lumpur, Kuala Lumpur, Malaysia; Vietnam

Department: STX - Engineering

About the Role

We are looking for a Senior Backend Engineer to join our Card Issuing Team, which builds the APIs and infrastructure that let businesses launch and manage their own card programs across Southeast Asia. You will take ownership of a core domain within our live production platform, setting the technical direction and raising the engineering bar. This role suits someone who has run high-stakes production systems and is comfortable making architectural decisions with incomplete information.

What You Will Do

• Lead the technical design (writing RFCs) for high-availability money-moving systems, making critical decisions on scalability, consistency, and failure handling.

• Take full technical ownership of a core domain (e.g., authorization, settlement), balancing new product features with technical debt and reliability.

• Build and scale RESTful microservices, ensuring strict idempotency, reconciliation correctness, and security (PCI DSS) in every financial flow.

• Drive technical integrations with card networks, payment processors, and third-party providers.

• Partner with Product, QA, and Ops to break down ambiguous problems into deliverable work, while mentoring junior/mid-level engineers.

• Pioneer the use of AI tools and agents to safely automate engineering and operational workflows within a regulated payments environment.

What We Are Looking For

• 5+ years of backend engineering, with a strong track record of designing, launching, and operating high-scale or financial production systems.

• Expert-level Golang with deep experience building microservices deployed on modern cloud infrastructure (Docker, Kubernetes, CI/CD).

• Advanced SQL skills (MariaDB/MySQL), including query optimization, transactions, locking, and live schema migrations.

• Excellent debugging skills, sound judgment on technical trade-offs, and the ability to write clear technical documents to drive team alignment.

• Hands-on experience using AI-assisted development tools (like Claude or Cursor) to accelerate delivery without compromising code quality.

• Domain Knowledge (Bonus): Prior experience with payments, card issuing, settlement systems, network integrations (Visa/Mastercard, ISO 8583), or PCI DSS compliance is a strong plus.