Hire the Best API Developers
in Vietnam

I’ve been building web applications for more than 10 years, mostly for startups and SaaS companies. Most of the projects I join aren’t greenfield projects. They’re products that already have users, existing code, tight deadlines, and features that need to be shipped without breaking anything. That’s the kind of work I actually enjoy. Over the years I’ve worked on React, Next.js, Node.js, PostgreSQL, Supabase, AWS and Stripe integrations. Those are simply the tools I’ve used. What matters more to me is understanding how the product works before writing code. A few examples from recent projects: • Reduced checkout abandonment by 18% after redesigning part of the purchasing flow. • Cut infrastructure costs by around 35% by rebuilding the deployment pipeline and automating releases. • Built and maintained multi-tenant SaaS applications used by growing businesses. • Integrated Stripe, Salesforce and third-party APIs into existing production systems. One thing clients often tell me is that I get up to speed quickly. I don’t need weeks to understand an existing codebase. I ask questions, understand how the system works, and start contributing as early as possible. I’m also comfortable working directly with founders, designers and product managers. Sometimes that means discussing technical solutions, and sometimes it simply means pointing out a cheaper or simpler way to build something. If you’re looking for someone to help move your product forward instead of just completing tickets, I’d be happy to have a conversation.

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.

🏆 Upwork Top Rated Plus Talent (July 2023 – Present) 🏆 Upwork Top Rated Talent (Feb 2022 – July 2023) ⚡ $100K+ earned on Upwork within 4 years I specialize in optimizing, building, and scaling Zoho solutions and automation systems that significantly enhance business performance. As a leading Zoho developer in Vietnam with strong C# expertise, I help businesses streamline operations, improve data accuracy, and unlock growth through well-architected systems and intelligent automation. 🔹 Zoho Solutions & Business Automation 1. Design and implement end-to-end Zoho One ecosystems (CRM, Books, Inventory, Projects) 2. Build advanced customizations using Deluge, Client Scripts, and Widgets 3. Develop seamless integrations with third-party platforms (Stripe, Xero, Twilio, RingCentral, Shipping APIs) 4. Engineer robust workflows, validation logic, and automation to ensure efficiency and data integrity 🔹 AI & Intelligent Automation 1. Integrate LLMs (ChatGPT, Gemini) into business workflows 2. Automate document processing (OCR) and client communication 3. Convert unstructured data (PDFs, emails) into structured, actionable insights 🔹 Full-Stack Development (C# / .NET) 1. Develop scalable enterprise applications using ASP.NET Core and modern .NET 2. Apply SOLID principles and design patterns (MVC, DI, Repository) 3. Design efficient database architectures with Entity Framework Core and SQL optimization 4. Build clean, high-contrast UI with React and Ant Design 5. Deploy and manage solutions on Azure and AWS My goal is simple: build systems that don’t just work — but actively support and accelerate your business growth.

👨‍💻 Backend Node.js Developer (5+ years) specializing in high-performance systems, AI/LLM integration, and secure API architecture. 🛠️ Core Tech Stack: Node.js, NestJS, Express, TypeScript, PostgreSQL, MongoDB, Redis 🔌 Integration Expert: Deep experience with third-party payment systems, disbursement APIs, and secure webhook architectures 🚀 Production-Ready: I don't just ship features — I build secure, maintainable backend systems that survive real-world traffic 🤝 Technical Partner: I bridge the gap between business requirements and clean, scalable backend code As a Backend Node.js Developer, I'm the person you call when you need to move from a prototype to a production-grade system — whether it's architecting a complex payment flow, integrating LLM/RAG capabilities into your product, or stabilizing a backend that's struggling to scale. I focus on the "how" as much as the "what." Here is how I add value to your project: 1. Backend & API Architecture (Node.js, NestJS, Express) Designing robust APIs that handle authentication, complex permissions, and business logic. Specialized in secure third-party integrations — payment gateways, disbursement systems — including signature generation and sandbox-to-production migration. 2. AI & LLM Integration (RAG, Vector Search) Building RAG pipelines — document ingestion, embedding, retrieval — and integrating LLM-based agents into production workspaces, backed by custom evaluation harnesses to test and tune retrieval quality. 3. Database & Infrastructure (PostgreSQL, MongoDB, Redis) Designing relational and NoSQL schemas that actually scale. Optimizing queries and implementing caching layers to keep your app fast as your data and user base grow. Track record of cutting infrastructure costs by 30-40% through targeted optimization. 4. Microservices & Clean Architecture Architecting API gateways and service boundaries for complex, multi-team systems — applying Clean Architecture and DDD principles so your codebase stays maintainable as it grows. 5. System Security & Reliability Implementing secure backend standards to prevent common vulnerabilities and unauthorized access. Managing background jobs and async processing that stay stable as requirements evolve. Technical Toolbox Backend: Node.js, Express, NestJS, Loopback, TypeScript Database: PostgreSQL, MongoDB, Redis AI/LLM: RAG pipelines, Pinecone, LLM APIs, custom evaluation harnesses Integrations: Payment APIs, Disbursement Systems, RESTful Webhooks, gRPC Tools: Git, CI/CD, Postman, Linux When we work together, you aren't just hiring a coder — you're hiring an engineer who cares about the security and longevity of your backend. I make the technical trade-offs early so you don't pay for expensive rewrites later. 🔑 Keywords: Backend Developer, Node.js Developer, NestJS Developer, TypeScript Developer, API Developer, Microservices Architect, PostgreSQL Developer, MongoDB Developer, Redis, RAG Developer, LLM Integration, AI Backend Engineer, Payment Integration Developer, Cloud Deployment, Software Architecture, Startup Backend

🚀 Transform your ideas into fast, scalable web applications. I’m a Laravel & WordPress Developer specialized in building custom web apps, API integrations, and SaaS platforms from the ground up. Whether you need a clean backend architecture or a pixel-perfect frontend, I can help you bring your project to life — fast, secure, and maintainable. 🔧 What I can do for you: • Build and deploy full-stack Laravel applications (multi-tenant, SaaS, admin dashboards) • Create and integrate RESTful APIs (Stripe, Google, CRM, etc.) • Develop and customize WordPress themes & plugins • Migrate or connect WordPress with Laravel backend • Optimize performance and fix critical bugs in existing systems 💼 Tech Stack: Laravel, PHP, MySQL, WordPress, REST API, TailwindCSS, React, JavaScript, Docker, Git 🧠 I focus on writing clean, modular, and well-documented code — so your project stays easy to maintain and scale over time. 💬 Let’s discuss your idea — I’ll help you turn it into a robust web solution that delivers real results.

PHP & MYSQL | NODEJS | WORDPRESS | WOOCOMMERCE | LARAVEL | CODEIGNITER IOT | ESP32 | ARDUINO | Raspberry Pi | STM32 I’m a senior full-stack developer with 15+ years of experience building websites, web applications, custom business systems, and integrations. I work across both frontend and backend, which allows me to understand the full picture of a project — from database structure, backend logic, APIs, and performance, to clean user interfaces and smooth user experience. What I can help with: • Custom WordPress and WooCommerce development • PHP, Laravel, CodeIgniter, and Core PHP development • React, Vue, Angular, JavaScript, HTML, CSS, and jQuery • Node.js backend development • API development and third-party integrations • Payment gateway integrations such as Stripe and eWAY • CRM, booking, membership, and custom workflow systems • Database design, optimization, and migration • Bug fixing, performance improvement, and server-side troubleshooting • Hybrid mobile app development with React Native, Ionic, and Cordova I focus on writing clean, maintainable, and scalable code. I also help clients make practical technical decisions, avoid unnecessary complexity, and build systems that are easier to manage and extend in the future. Over the years, I’ve worked on many types of projects — from small business websites to complex custom platforms. I’m comfortable joining an existing project, fixing difficult issues, improving performance, or building a new product from the ground up. If you’re looking for a reliable senior developer who can handle both the technical details and the bigger picture, feel free to invite me to your job. I’d be happy to discuss your project.