Senior Golang Developer

Top 3 Reasons To Join Us The Job The Operation Platform team is responsible for centralizing and scaling all operational aspects of Lumen Dynamics , one of Vietnam’s leading financial platforms. Our mission is to build a unified, reliable, and extensible operation ecosystem that empowers operations teams to efficiently support millions of users, merchants and partners . Within this platform, the Merchant Operation domain focuses on everything that happens after an online payment succeeds . This includes clearing and settlement, payouts, merchant wallets, payment request approvals, and operational tools that ensure funds move accurately, transparently, and on time. We design systems that sit at the intersection of technology, finance, and operations , where correctness, traceability, and scalability are equally critical. By reusing common components and standardizing operational logic, we aim to make daily operational work simpler, safer, and more efficient. We are looking for a Senior Software Engineer (Golang) who enjoys building reliable backend systems in financial domains and understands the challenges of operating large-scale, data-heavy platforms. Responsibilities You will: Design, build, and maintain backend systems for merchant operation domains , including: Clearing, settlement, and payout flows Merchant wallet and balance management Payment request approval and operational workflows Build and evolve data-intensive services that handle large volumes of operational and financial data. Design reusable components and shared services to support multiple operational use cases across Lumen Dynamics. Ensure data correctness, idempotency, auditability, and consistency in post-payment workflows. Work with multiple storage and data systems, such as: Relational databases for transactional data TiKV or similar distributed KV stores for high-throughput, low-latency use cases Elasticsearch for search, investigation, and operational dashboards Design batch and file-based integration flows using HDFS, FTP/SFTP , and scheduled jobs for reconciliation, settlement, and partner integrations. Improve system observability and traceability to support operations, reconciliation, and issue investigation. Collaborate closely with Product, Operations, Finance, and other Engineering teams to deliver end-to-end solutions. Debug and resolve complex production issues related to merchant operations and fund movement. Contribute to technical standards, code quality, and best practices within the Operation Platform team. Your Skills and Experience You may be a good fit for this role if you: Hold a Bachelor’s or Master’s degree in Computer Science, Software Engineering, or a related field. Have at least 3 years of experience in backend software development. Have strong proficiency in Golang . Have solid experience in backend system design , including API design, data modeling, and service decomposition. Have strong knowledge of relational databases and SQL , including transactions, indexing, and performance tuning. Have hands-on experience with NoSQL or distributed data systems such as MongoDB or TiKV. Understand distributed system concepts such as idempotency, concurrency control, eventual consistency, and failure handling . Have experience using Redis or similar caching systems. Are comfortable working with large datasets, batch jobs, and file-based data exchanges (e.g. HDFS, FTP/SFTP). Have experience diagnosing and tracing production issues in large-scale systems. Write clean, maintainable, and well-tested code. Nice to have: Experience in FinTech, payments, merchant platforms, or accounting-related systems . Hands-on experience with clearing, settlement, payout, reconciliation, or wallet systems . Experience building or maintaining operational tools, approval workflows, or investigation dashboards . Experience with Elasticsearch for searching, reporting, and operational analysis. Familiarity with event-driven architectures (Kafka or similar). Experience running systems in Kubernetes or cloud-native environments . Ability to work closely with non-technical stakeholders (Operations, Finance) and translate business workflows into technical solutions. Why You'll Love Working Here Established in 2017, Lumen Dynamics is a key member of VNG Corporation - Vietnam's technology champion. Driven by a mission to elevating all things money, we’ve become one of Vietnam’s leading payment platforms, making transactions seamless for everyone - every need, every time, everywhere, and everything. By the end of 2024, over 16 million users have trusted Lumen Dynamics, benefiting from a diverse ecosystem of 100+ services. We are also the only Vietnamese fintech recognized on CNBC’s Top 200 Global Fintech Companies. At Lumen Dynamics, we foster a dynamic workplace where talent drives impactful fintech innovations, empowering you to push limits and elevate your career. Join us and be part of something bigger!