Senior Backend Java Engineer

Job OverviewJob title: Senior Backend Engineer – PlatformDirect Manager: Lead Software EngineerWorking Location: Lottery Tower, 77 Tran Nhan Ton, An Dong Ward, HCMCEstablished in 2019 as Vietnam’s pioneering Buy Now, Pay Later provider, Fundiin is evolving into a data-first, AI-enabled platform for financial services in 2026. Fundiin partners with leading banks and financial institutions to orchestrate and optimize the distribution of a wide range of products—from BNPL and personal loans to credit cards—through a single and seamless app.Leveraging proprietary data and AI-driven decisioning, Fundiin matches consumers with the most relevant offers, improving approval rates, user experience, and bank/lender performance. By delivering a fully digital, end-to-end journey, Fundiin enables millions of users to access financial products with greater clarity, confidence, and control.Job SummaryWe are looking for a Senior Backend Engineer – Platform to design, build, and evolve the shared technology foundation that powers Fundiin’s financial products and bank/lender ecosystem.In this role, you will develop secure, reliable, and reusable platform capabilities across customer and bank/lender services, product and application orchestration, transactions, integrations, events, data access, and operational tooling. You will work closely with Product, Engineering, Risk, Data, Security, and Operations to enable multiple financial products and banks/lenders to scale through consistent APIs, platform standards, strong observability, and operational excellence.This is a hands-on engineering role with platform-level ownership. You will contribute to architecture and technical direction, deliver production-grade services, improve engineering standards, and mentor other engineers.AccountabilitiesPlatform Architecture and EngineeringDesign, build, and maintain shared backend capabilities that support multiple Fundiin products, channels, and bank/lender integrations.Evolve the existing backend toward domain-aligned services and a scalable platform architecture, including service boundaries, APIs, data models, event contracts, migration strategies, and backward compatibility.Build reusable platform services and standards for customer and bank/lender management, product configuration, application orchestration, transactions, notifications, reporting, and auditability.Define and maintain clear, versioned API and event contracts that enable product teams and external banks/lenders to integrate safely and efficiently.Make pragmatic architecture decisions that balance delivery speed, scalability, maintainability, cost, and operational risk.Bank/Lender Integration PlatformDesign and enhance the integration layer for banks, lenders, payment providers, and merchants.Standardize bank/lender-specific behaviors behind stable platform contracts, including authentication, request and response mapping, webhooks, retries, timeouts, idempotency, reconciliation, and error handling.Improve bank/lender onboarding through reusable connectors, configuration-driven capabilities, integration documentation, test environments, and operational monitoring.Ensure transaction and application flows remain traceable, recoverable, and consistent across distributed systems and external dependencies.Reliability, Security, and OperationsBuild services for high availability, resilience, performance, and safe degradation, with appropriate use of caching, asynchronous processing, circuit breakers, rate limits, and failure recovery patterns.Define and improve service-level indicators and objectives, dashboards, alerts, logs, metrics, and distributed tracing for critical platform journeys.Participate in incident response, root-cause analysis, capacity planning, and continuous improvement of production systems.Apply secure-by-design practices, including least-privilege access, secrets management, encryption, protection of personal and financial data, audit trails, and secure API design.Support internal security, risk, and compliance requirements through reliable controls, evidence, and traceability in platform services.Data and Event Platform EnablementPartner with Data Engineering to define and implement reliable event and data contracts, schema evolution practices, and unified data models.Build data access services and operational data flows that provide trusted, timely information for products, risk decisioning, analytics, reporting, and bank/lender operations.Enable secure and reliable integration of AI/ML capabilities into platform services, including service contracts, access controls, observability, fallbacks, and protection of sensitive data.Improve data quality, lineage, observability, and ownership at the source while protecting sensitive customer and financial information.Developer Experience and Engineering ExcellenceImprove the developer experience through shared libraries, service templates, CI/CD standards, automated testing, local development tooling, documentation, and self-service platform capabilities.Establish and promote engineering standards for code quality, API design, testing, observability, deployment, and production readiness.Automate repetitive engineering and operational workflows to reduce lead time, manual errors, and dependency on individual teams.Track platform adoption, reliability, and delivery effectiveness, and use these signals to prioritize platform improvements.Cross-Functional Collaboration and Technical LeadershipWork with Product, Engineering, Risk, Data, Security, Operations, and bank/lender-facing teams to translate business needs into scalable platform capabilities.Lead technical discovery, architecture discussions, design reviews, and implementation planning for complex cross-team initiatives.Mentor engineers, provide constructive code and design feedback, and help teams make sound technical trade-offs.Communicate technical decisions, risks, dependencies, and operational impacts clearly to both technical and non-technical stakeholders.Qualifications & ExperienceEducationBachelor’s degree in Software Engineering, Computer Science, or a related field, or equivalent practical experience.Required Experience and Domain Expertise4-5+ years of professional backend software development experience, including ownership of production systems.Strong hands-on experience with Java and the Spring ecosystem, including Spring Boot, Spring Data JPA/Hibernate, and RESTful services.Proven experience designing distributed systems, platform services, or reusable backend capabilities used by multiple teams or products.Strong knowledge of object-oriented design, data structures, algorithms, software design principles, and common distributed-system trade-offs.Solid experience designing relational database schemas and optimizing SQL performance, preferably with PostgreSQL, Oracle, or SQL Server.Practical experience with microservices and event-driven architecture, including REST APIs, Kafka or RabbitMQ, Redis, transaction boundaries, eventual consistency, Saga or Outbox patterns, and idempotent processing.Experience with cloud infrastructure on GCP, AWS, or Azure, plus containerized deployment using Docker and Kubernetes.Experience with CI/CD, automated testing, and production observability using logs, metrics, traces, dashboards, and alerts.Proficiency with AI-assisted software development tools such as Claude, Codex … or equivalent to accelerate delivery while maintaining code quality, security, testing, and human review standards.Working knowledge of application security, API security, secrets management, and protection of personal or financial data.Strong ownership, analytical thinking, communication, and cross-functional collaboration skills in an Agile product development environment.Preferred QualificationsExperience in fintech, banking, lending, payments, financial services, or another regulated industry such as e-commerce, logisticsPrefer candidates born in 1996 or later.Experience building integration platforms, API gateways, bank/lender connectors, workflow or orchestration engines, or internal developer platforms.Experience integrating AI/ML services, LLM APIs, model-serving platforms, vector search, or similar AI capabilities into production systems.Experience with infrastructure as code, GitOps, service mesh, schema registry, contract testing, or Testcontainers.Experience operating high-volume, business-critical systems and participating in on-call or incident-response practices.Experience mentoring engineers or leading technical delivery across multiple teams.Professional working proficiency in English is an advantage when collaborating with technology vendors and banks/lenders.BenefitsWhy You’ll Love Working With UsAt Fundiin, we believe in fostering a dynamic work environment that encourages personal and professional growth.Empowerment and GrowthWe offer great autonomy, freedom to make decisions, and room to take risks and learn from mistakes.Get involved from the ground up in creating and developing new products, leading teams, working on innovative projects, and gaining visibility within the industry.Competitive BenefitsEnjoy a robust benefits package, including meaningful ESOP options.Access our premium health care program and annual health checkup.Receive a budget of 2,400,000 VND per year for professional development.Take advantage of device allowances or financing options covering up to 50% of new device purchases.Engaging Work EnvironmentParticipate in our monthly Town Hall meetings and collaborative sharing sessions.Enjoy 15 days of annual leave to recharge and pursue personal interests, plus an extra day for every 3 years of service.Join biannual team-building trips for bonding and connections.Enjoy free daily drinks and weekly TGIF snacks and beverages.