Hire the Best Java Developers
in Vietnam

Senior Backend Engineer with 10+ years of experience designing and building scalable backend platforms and cloud-based distributed systems. Strong expertise in Java, Spring Boot, and microservices architecture with production deployments on AWS. Experienced in building high-availability APIs, event-driven systems, and real-time services. Proven ability to improve system performance, reliability, and security while collaborating with global engineering teams. TECHNICAL SKILLS Languages: Java (8–17), JavaScript Backend: Spring Boot, Spring MVC, JPA, Hibernate, Google Guice, REST APIs, Microservices, WebSocket Frontend: AngularJS, Angular, React Messaging: Kafka, RabbitMQ Cloud & Infrastructure: AWS (EC2, S3, SQS, SNS, Lambda, Cognito, SES), Docker Databases: PostgreSQL, MySQL Observability: Elasticsearch, Logstash, Kibana (ELK) Security: OAuth2, JWT, Keycloak, OWASP Top 10 DevOps: Jenkins, Azure DevOps, Git, Bitbucket

Software Engineer with 4 years of experience specializing in backend development, distributed systems, and applied ML integration. Skilled in Java, JavaFX, Rust, PostgreSQL, SQLite, Spring Boot, Google Cloud, and Kubernetes, with a track record of optimizing performance and delivering high-quality software solutions. Fluent in English, with experience working with offshore teams and clients across both fields, delivering clear and effective communication across cultural boundaries.

Commitment – Professionalism – Respect Hi there! I’m Giang. I’m new to Upwork, but not new to building real products. Outside this platform, I’ve delivered web applications from scratch to production for businesses of all sizes. Clean code, Code Quality & Optimization, Performance Engineering and systems that actually work – that’s my standard. Tech I master (daily used): - Java (Spring Boot) | NodeJS | C# (.Net Core) | ReactJS, NextJS | VueJS | TypeScript - SQL/NoSQL, REST APIs, DDD, Agile/Scrum - Testing (unit/integration) is part of my workflow – not an afterthought. I speak English & Japanese (conversational). Let me prove my value on a small milestone first. I’m available to start within 24h

Senior Java / Spring Boot developer with 1,000+ Upwork hours, 37 completed projects, a 100% Job Success Score, and a 4.9/5 client rating. I specialize in backend development, REST APIs, API integrations, and maintaining or extending existing Java/Spring applications. One of my long-term Upwork engagements has lasted 4+ years and 850+ hours, supporting and developing a Java open-source project. I’m comfortable working with existing codebases, understanding unfamiliar systems, fixing bugs, adding features, and delivering maintainable solutions without unnecessary rewrites. What I can help you with: • Java / Spring Boot backend development • REST API design and development • Spring MVC / Spring Framework • Hibernate / JPA and SQL • Third-party API integrations • Backend bug fixing and troubleshooting • Existing codebase maintenance and feature development • Refactoring and improving legacy Java applications • Unit testing with JUnit • Node.js backend development • React when full-stack work is required I’m particularly comfortable with projects where you already have an application and need an experienced developer to understand the codebase, fix issues, implement new features, or continue development. I value clear communication, clean code, practical solutions, and long-term collaboration. If you have an existing Java/Spring project that needs development or maintenance, send me the details and I’ll take a look.

Senior Fullstack Software Engineer | Java, Node.js, React | CMS & IoT Expert 🚀 About Me I am a Senior Fullstack Software Engineer with 4+ years of experience in developing high-performance web applications, CMS platforms, and IoT solutions. My expertise spans across Java Spring Boot, Node.js, React, Magnolia CMS, and cloud-based architectures. I have led teams, optimized complex systems, and built scalable solutions for enterprise-level clients. 🔹 Backend: Java Spring Boot, Node.js, NestJS, Microservices, GRPC 🔹 Frontend: React.js, React Native, Headless CMS 🔹 CMS: Magnolia CMS, Liferay, WordPress 🔹 Databases: MySQL, MongoDB, SQL Server 🔹 DevOps & Cloud: Docker, Kubernetes, GitLab CI/CD, AWS 🔹 IoT & AI: Zigbee, MQTT, OpenCV, AI-based detection systems 💼 Notable Projects ✅ MMP’s CMS Website: Built a Java Spring Boot-based CMS optimized for high traffic and large datasets. ✅ Dentsu’s Headless CMS: Developed a scalable API-driven CMS using Magnolia CMS and React. ✅ Yoolife & YooIOC Applications: Smart city applications for residential and operational management. ✅ IoT Platform for Smart Devices: Developed a gateway integrating Zigbee, Z-Wave, and BLE devices with AI-powered event detection. 🔍 Why Work With Me? ✔ Proven expertise in enterprise CMS solutions & IoT systems ✔ Strong problem-solving skills in system architecture & optimization ✔ Experience leading development teams & mentoring junior engineers ✔ Passionate about building scalable, high-performance applications Let’s connect and bring your ideas to life! 🚀

Technical Leadership: Driving architectural decisions, designing microservices, and ensuring code quality across the full stack. Backend Development: Expertise in Java (8+), Spring Boot, Hibernate, API design (REST/SOAP/gRPC), and database management (SQL/NoSQL). Frontend Development: Developing responsive, user-facing interfaces using frameworks like React or Angular. System Design & Optimization: Creating secure, scalable applications and improving performance. CI/CD & DevOps: Utilizing tools like Docker, Kubernetes, Terraform, and Jenkins for deployment, OpenSearch, RabbitMQ, Kafka, Kibana. Experiences with AI technology, Clause Code, Cursor, Copilot, Bedrock