Senior Software Engineer - Experiments

Xendit provides payment infrastructure across Southeast Asia, with a focus on Indonesia, the Philippines and Malaysia. We process payments, power marketplaces, disburse payroll and loans, provide KYC solutions, prevent fraud, and help businesses grow exponentially. We serve our customers by providing a suite of world-class APIs, eCommerce platform integrations, and easy to use applications for individual entrepreneurs, SMEs, and enterprises alike.

Our main focus is building the most advanced payment rails for Southeast Asia, with a clear goal in mind — to make payments across and within SEA simple, secure and easy for everyone. We serve thousands of businesses ranging from SMEs to multinational enterprises, and process millions of transactions monthly. We’ve been growing rapidly since our inception in 2015, onboarding hundreds of new customers every month, and backed by global top-10 VCs. We’re proud to be featured on among the fastest growing companies by Y-Combinator.

About the Job

The Experiments team builds growth engines for Xendit through experimental products. We do this by pushing the frontiers of what is possible in the industry and creating modern solutions to old problems. As part of the Experiments team, you may become part of a team that builds from 0 to 1, from 1 to 1,000, or 1,000and beyond. It requires flexibility and adaptability to take on new challenges to grow an early-stage product or market

To build from the ground up, we take ideas, customer pain points, or gaps in the market, push out an MVP at speed, and iterate to find product-market fit. This team presents a unique opportunity for people looking to build something new, rather than scaling mature products. People who join this team have a strong interest in growth (personally and professionally) and, therefore, a continuous improvement mindset

Given the experimental nature of our work, we often build across multiple domains and collaborate closely with other teams’ systems and services. This means coordinating with service owners, understanding their architecture and constraints, and co-developing solutions that integrate seamlessly into the broader ecosystem—requiring both technical versatility and strong communication skills.

We're seeking a passionate individual to be a Senior Software Engineer in our Experiments team. This role will specifically focus on expanding our offerings to new markets. This involves building deep domain knowledge and expertise in our current system and expanding it beyond SEA. Do whatever it takes to make Xendit successful!

Minimum Qualifications

• > 6 years of software engineering experience in post-A round startups or scale-ups

• Demonstrated technical leadership, influence, and autonomy while delivering complex, customer-facing features at scale

• Solid grasp of security and authentication requirements

• Strong expertise in NodeJS Typescript, and Golang

• Deep understanding of REST and event-driven (pub/sub) pattern

• Experience with SQL and NoSQL databases, schema design, and query optimization.

• Familiarity with message brokers (Kafka, SQS, etc.) and cloud technologies

• Strong testing discipline (unit, integration, E2E with Jest, Mocha, Supertest, etc.)

• Exceptional verbal and written communication skills in English

• Comfortable operating in Agile environments, balancing speed and reliability

• Experience with Observability tools (i.e.: Datadog, Splunk)

Preferred Qualifications

• Payments experience at scale is a plus

• Proven experience designing and developing high-availability, idempotent payment systems

• Solid grasp of compliance requirements for financial systems

• Familiarity with containerization and orchestration (Docker, Kubernetes)

• Ability to refactor or modernize legacy systems

• Exposure to multi-region architectures or serverless approaches

• Experienced with Domain-Driven Design