Java Backend
Java, Spring Boot, Spring MVC, Spring Data JPA, Spring Security, Hibernate, REST APIs, transactions, JUnit, and Mockito.
Backend engineering profile
Senior Backend Engineer building Java/Spring Boot and Python/FastAPI systems
I bring 10+ years of software engineering experience across enterprise integrations, SaaS APIs, transactional workflows, security, billing, asynchronous processing, and AI services. Java/Spring Boot and Python/FastAPI are my primary backend stacks, with ownership from architecture and testing through production support and reliability.
Selected backend product demo
ProdReadyAI / Jobs Work — Live SaaS Backend Demo
A live Python/FastAPI SaaS system integrating OpenAI and Google Gemini with deterministic validation, guardrails, Firebase authentication, protected APIs, and Stripe subscriptions with webhook-backed billing synchronization.
Built a production-oriented SaaS backend reference covering authentication, subscription billing, AI workflows, protected APIs, and cloud deployment. The system uses Python and FastAPI for AI services integrating OpenAI and Google Gemini, with deterministic validation, guardrails, and reliable failure handling. Node.js and Next.js are used as a secure same-origin BFF for authentication propagation, protected request forwarding, Stripe billing flows, Firebase Authentication, and private backend access.
Core backend capabilities
Backend systems designed for real production constraints
Primary Java and Python engineering, backed by enterprise integration, data, security, messaging, cloud, and testing experience.
Python Backend and AI Services
Python, FastAPI, Django, SQLAlchemy, Pydantic, OpenAI, Google Gemini, AI microservices, ETL, background processing, and Pytest.
Enterprise Architecture and Integrations
Microservices, layered architecture, service boundaries, ERP, CRM, telecom, logistics and payment integrations, synchronization, idempotency, and retries.
SaaS, Billing, and Security
Stripe, Firebase Authentication, JWT, OAuth, RBAC, tenant isolation, subscription lifecycles, webhooks, and backend-enforced authorization.
Data and Persistence
PostgreSQL, Oracle, MySQL, MongoDB, HiRDB, JPA, Hibernate, SQLAlchemy, indexing, query optimization, caching, and migrations.
Messaging and Background Processing
Kafka, message queues, scheduled jobs, cron workflows, event processing, state reconciliation, and failure recovery.
Cloud, DevOps, and Testing
Docker, Kubernetes, Google Cloud Run, Cloud SQL, AWS, GitHub Actions, CI/CD, monitoring, rollback, and integration testing.
BFF and Limited Frontend Exposure
Node.js and TypeScript support Next.js BFF, API proxying, request forwarding, and authentication propagation. React and Next.js exposure is limited to backend integration.
Professional experience
A decade of backend delivery and production ownership
Selected evidence from enterprise, telecom, healthcare, business systems, and SaaS work.
Confidential U.S.-Based AI SaaS Startup
Senior Backend Engineer — Java, Python and AI Systems
Remote — United States
Feb 2026 – Present
- Build Java/Spring Boot services with Spring Data JPA, Spring Security, Hibernate, PostgreSQL, transaction-safe billing, authentication, and entitlements.
- Deliver asynchronous and scheduled processing plus Python/FastAPI AI services integrating OpenAI and Google Gemini.
- Use Node.js/TypeScript only as a BFF, deploy on Google Cloud, test across Java and Python, and contribute limited React/Next.js integration work.
Hotlink / Maxis
Technical Leader — Java Backend and eCommerce Integration
Remote — Malaysia
Apr 2023 – Dec 2025
- Led Java Spring Boot telecom and eCommerce services spanning payments, catalogs, logistics, CRM, and reporting.
- Applied Spring Data JPA, Hibernate, Spring Security, Kafka, scheduled processing, and Python ETL, automation, and AI workflows.
- Ran containerized production services with Docker and Kubernetes; Node.js/TypeScript remained limited to BFF and integration boundaries.
Zuellig Pharma
Technical Leader — Golang Microservices and Healthcare Commerce
Remote — Singapore
Jul 2021 – Mar 2023
- Led development and integration for a B2B healthcare commerce platform used by hospitals, clinics, distributors, vendors, warehouse teams, and operational users across Asia.
- Built Golang microservices and REST/GraphQL APIs for product, order, inventory, warehouse, logistics, vendor, and ERP workflows, integrating operational data from more than 30 vendors using PostgreSQL and MongoDB across persistence and data-access layers, with Kafka event processing, retry handling, idempotency, and reconciliation.
- Built React interfaces with SCSS for order management, inventory visibility, warehouse operations, and backend API integration, and containerized Golang and React applications using Docker and Kubernetes with GitHub Actions CI/CD.
Aurecon Group
Backend Engineer — Java and Python Business Systems
Remote — Australia
Oct 2020 – Jun 2021
- Built Java Spring Boot business systems with PostgreSQL, Spring Data JPA, Hibernate, REST APIs, and scheduled jobs.
- Created Python automation and reporting workflows that saved more than 15 hours of manual work each week.
- Tested and deployed through Docker and Kubernetes, using Node.js/TypeScript only for lightweight BFF integration.
NTT Communications
Java Backend Engineer — Spring MVC and Data Processing Systems
Onsite — Japan
Jan 2018 – Aug 2020
- Developed Java Spring MVC and Hibernate telecom and enterprise systems with transactions, integrations, and production diagnostics.
- Built Python data-processing utilities and a TensorFlow facial-recognition service for a production pilot.
- Built lightweight internal integration utilities and limited JavaScript/React interfaces while keeping Java backend systems central.
KDDI Corporation
Java Backend Engineer — Enterprise Systems
Onsite — Japan
Mar 2015 – Dec 2017
- Built enterprise transaction and caching systems with Java, Spring MVC, Struts, Hibernate, and Ehcache.
- Operated Oracle and HiRDB workloads, including multi-terabyte database operations under strict SLAs.
- Supported production reliability and recurring operations with Python automation and limited JavaScript exposure.
Work with me
I work best with teams that need strong engineering ownership.
If you need senior backend ownership across Java, Python, enterprise integrations, SaaS APIs, AI systems, and production reliability, feel free to reach out.