Senior Software Engineer, Backend

Xenith; Jakarta Pusat; On-site; IDR 420,000,000 - 750,000,000; Full time

Job summary

Xenith is a B2B fintech platform seeking an experienced Go backend engineer. You will design, build, and maintain scalable services, integrate with payment providers, and ensure robust tests and security.

You will mentor engineers and uphold clean architecture while delivering high-impact features for a fast-growing fintech environment. You will collaborate across product, infra, and QA to ship reliable payments software, deploy on AWS, and drive observability and performance improvements.

Qualifications

• Bachelor's degree in Computer Science or a related field.
• 5+ years backend engineering experience with production Go.
• Proven track record of integrating with external APIs, especially in payments/fintech.
• Strong system design and test-driven development.
• Experience with PostgreSQL and Redis in high-availability environments.
• Experience with test automation.
• Strong communication skills for stakeholders.
• Familiarity with Agile practices and continuous improvement.
• Security-conscious mindset; OWASP awareness.
• Demonstrated leadership in mentoring peers.
• Excellent English communication and documentation.

Responsibilities

• Design, develop, and maintain scalable backend services using Go with emphasis on code quality and maintainability.
• Integrate with third-party payment services (banks, e-wallets) and handle edge cases.
• Write robust unit and integration tests for new features and ensure validation of critical payment flows.
• Collaborate with product, infra, and QA to define, design, and ship features.
• Mentor junior and mid-level engineers through code reviews and design discussions.
• Lead by example with clean architecture, documentation, and observability practices.
• Identify and resolve performance bottlenecks and improve system resilience.
• Stay current with new technologies and propose business-aligned improvements.
• Build software with security and auditing in mind.
• Deploy applications to AWS and support operational readiness.

Skills

Go

Backend design

API integration

PostgreSQL

Redis

Testing

Security

Leadership

Agile practices

English

Education

Bachelor's degree in Computer Science

Job description

What we're looking for

We are seeking a talented, endlessly curious individual to join our team. You’ll be working closely with our group of companies in the fintech sector as part of the Engineering department. This company is a leading B2B fintech platform in its field, processing over US$2B across multiple currencies annually. We’re looking for individuals who are driven to create meaningful value, take full ownership of what they build, and thrive in a fast-paced, high-growth environment. If you’re motivated by impactful work and eager to be part of an innovative team, we’d love to hear from you.

What you’ll do

• Design, develop, and maintain scalable backend services using Go, with a strong emphasis on code quality and maintainability
• Integrate with third-party payment services (e.g. banks, e-wallets) and handle edge cases such as ambiguous or delayed responses
• Write robust unit and integration tests for all new features and ensure proper validation for critical payment flows
• Collaborate cross-functionally with product, infra, and QA teams to define, design, and ship high-impact features
• Guide and mentor junior and mid-level engineers, providing technical leadership through code reviews, design discussions and pairing sessions
• Lead by example in enforcing clean architecture, clear documentation, and reliable observability practices
• Identify and resolve performance bottlenecks, improve system resilience, and optimize for correctness and traceability
• Stay up to date with emerging technologies and propose improvements aligned with business goals
• Build software with security and compliance in mind, ensuring proper access control, logging, and auditing
• Deploy applications to AWS infrastructure and support operational readiness of services

What you should have

• Bachelor's degree in Computer Science or a relevant field
• 5+ years of backend engineering experience, with production-level experience in Go
• Proven track record of integrating with external APIs, especially in payment, banking, or financial services
• Strong foundation in system design, test-driven development, and writing maintainable, well-documented code
• Comfortable working with PostgreSQL and Redis in high-availability environment
• Experience with test automation and methodologies for both unit and integration testing
• Strong communication skills - able to explain trade-offs clearly to both technical and non-technical stakeholders
• Familiarity with Agile practices and a commitment to continuous improvement
• Security-conscious mindset; familiarity with OWASP vulnerabilities and mitigation techniques
• Demonstrated leadership in team settings - mentoring, reviewing and leveling up peers
• Excellent communication and documentation skills in English.

About Us

Xenith is a B2B payment service provider focused on enabling seamless cross-border commerce. With an MSB license in Canada and PJP III license in Indonesia, we offer global merchants a one-stop solution to manage multi-currency payments - with a strong focus on alternative payment methods in emerging markets. Our deep regional expertise and strong partnerships with top local gateways, we simplify the complexity of fragmented payment landscapes, helping global merchants expand faster and more efficiently. At Xenith, we believe in building a culture where people feel empowered, trusted, and challenged to do their best work. Join us as we build the financial infrastructure of tomorrow!