Hire the Best DevExpress Developers
in Vietnam

What if your web application was fast, scalable, secure, and built to support future growth...without you wasting time fixing unstable code, broken APIs, or deployment issues? Reading this means you need help with .NET Full Stack Development, ASP.NET Core, C#, React, Microsoft Azure, AWS or AI Integration, and you want a developer who can turn your idea into a reliable, production-ready solution.

If you need a veteran developer to build robust business applications, AI-powered solutions, desktop software, or custom tools that interact with major marketplaces, let's talk. With 25+ years of software engineering experience, my core strength is building reliable business applications backed by high-performance SQL Server databases. I also develop AI solutions using Microsoft Semantic Kernel, OpenAI, and .NET, including AI assistants that use kernel functions to work with real business data. CORE TECHNICAL EXPERTISE: • AI & Semantic Kernel: Building AI assistants with Microsoft Semantic Kernel, OpenAI, kernel functions, automatic function calling, AI-to-SQL data integration, and function invocation logging. • Desktop Applications (Windows & Mac): Expert in Windows Forms, C#, VB.NET, DevExpress, and native macOS development using Objective-C. • Database & Backend: SQL Server, T-SQL, database design, optimization, REST APIs, and server management (Local, AWS, Azure). • Marketplace Integrations & Custom Tools: Developing automation software, inventory/order synchronization tools, and API integrations for Amazon (SP-API), Walmart, Best Buy, and Macy's. • Web, Mobile & Automation: .NET, TypeScript, Angular, REST APIs, Chrome Extensions, and Google Apps Script. BUSINESS DOMAINS: Warehouse & Freight Management, Barcode Technology (1D/2D), ERP/Accounting integrations, Retail & Wholesale, Customer Management, and Financial Systems. HOW I CAN HELP YOU: • Build AI-powered business applications using .NET, Semantic Kernel, OpenAI, and SQL Server. • Build, modernize, or scale custom Windows desktop applications and SQL databases tailored to your workflow. • Develop or troubleshoot automated tools and API integrations connecting your business systems to Amazon, Walmart, Best Buy, and other marketplaces. • Integrate AI into existing business applications and databases using controlled, reliable backend functions. Available for ~30 hours/week. If you need clean, reliable code and deep technical execution—with 25+ years of experience across business applications, databases, APIs, marketplaces, and AI integration—send me a message and let's discuss your project.

✅ Top-Rated Senior Developer ✅ 100% Job Success Score ✅ Available for part-time, full-time long-term projects on Upwork (up to 40+ hours/week) ✅ Government ID Verified ✅ Professional Experience ✅ Expertise in .NET-based Web Applications, RESTful APIs, SPA architectures, CMS solutions, and enterprise-grade systems I’m a Senior Full-Stack .NET Developer with 6+ years of hands-on experience delivering and optimizing production-ready applications using C#, ASP NET / .NET Core, ABP Framework, and frontend technologies such as Angular, React, and modern JavaScript frameworks. I work across both backend and frontend, focusing on APIs, database design, performance optimization, and building responsive, user-friendly interfaces. What I Help You With - Custom web applications & system upgrades - Secure, efficient API integrations - Performance optimization & code refactoring - Long-term maintenance & scalability improvements Technical Expertise - Backend: C#, ASPNET MVC/Core, Web API, EF/EF Core, ABPio - Frontend: Angular, React, Vue, Blazor WASM, Nextjs, Tailwind, Telerik/Kendo UI - Databases: SQL Server, Azure SQL, MySQL, PostgreSQL, MongoDB - Cloud & Tools: AWS, Azure, Git, Visual Studio, CI/CD - Platforms: Windows Server, Linux, macOS Why Choose Me ✔ Clean, scalable, and maintainable code ✔ Fast delivery without sacrificing quality ✔ Client-focused communication ✔ High-performance, real-world applications ✔ Money-back guarantee & long-term discounts Availability 🕒 Part-time or Full-time (40+ hrs/week) | Ready to start immediately 💬 Response within 1 hour | Flexible time zones 👉 Click “Hire Now” or “Invite to Interview” to get started. Best regards, Le Xuan Thuan

Hello, I’m Jason Nhien Truong, a Senior Software Engineer and Software Architect with over 20 years of professional experience delivering reliable, maintainable software solutions for businesses across multiple industries. I specialize in C# and .NET development, Windows desktop applications, enterprise web systems, SQL databases, and Azure-based platforms. I help clients modernize legacy systems, stabilize and scale existing products, and build new applications with a strong focus on performance, usability, and long-term maintainability. I work closely with stakeholders to translate business needs into practical, well-structured technical solutions. What I offer Full-stack .NET development I work across the .NET ecosystem, from legacy ASP.NET Web Forms to modern .NET 8 APIs and microservices. I design secure, scalable backend systems with clean architecture and clear separation of concerns. Windows desktop application development I have extensive experience building and maintaining Windows desktop applications using WinForms and WPF, including MVVM-based WPF applications. I focus on responsive UI behavior, clean data binding, maintainable ViewModel design, and user-friendly workflows for business-critical desktop software. Enterprise UI with DevExpress and Telerik I have deep expertise with DevExpress and Telerik controls for WinForms and web applications. I redesign and modernize complex UIs to improve usability, consistency, and performance without breaking existing business logic. Database architecture and optimization Strong experience with SQL Server, PostgreSQL, MySQL, and Azure SQL. I design schemas, optimize queries, and ensure data integrity and stability in production systems. Azure cloud and DevOps Hands-on experience deploying and maintaining applications on Azure, including CI/CD pipelines, containerized services, background processing, and cloud-based integrations. Testing and automation I write unit and integration tests using xUnit and NUnit, and implement automation with Selenium and AutoIt to improve quality and reduce regression risk. Key technical skills Languages and platforms C#, .NET Core, .NET 8, ASP.NET, SQL, JavaScript, HTML, CSS, Python Desktop development WinForms, WPF, MVVM, DevExpress WinForms, Telerik UI Frameworks and tools Entity Framework, LINQ, Docker, Azure DevOps Databases SQL Server, PostgreSQL, MySQL, MongoDB, Azure SQL Cloud and monitoring Azure, Kubernetes, Azure Service Bus, Prometheus, Grafana Architecture Microservices, Clean Architecture, Domain-Driven Design Selected projects Web forecasting application maintenance Maintained and enhanced a legacy ASP.NET Web Forms application using SQL Server 2022 and Telerik UI. Improved UI workflows, business logic, and performance. Betx – cloud-native microservices platform Developed backend microservices using .NET 8 and Web API. Worked on PostgreSQL data modeling, Azure Kubernetes deployment, secure APIs, messaging, and observability with Prometheus and Grafana. Custom ERP system for manufacturing Built a custom ERP system using C# and SQL Server, including workflows, reporting, role-based access, and third-party integrations. Carrier pricing API integration Integrated FedEx and UPS APIs for real-time pricing, data synchronization, and robust error handling with retries and logging. Why work with me I bring deep technical experience, strong ownership, and a business-focused mindset. I communicate clearly, meet commitments, and build software that remains stable and maintainable over time. Availability Open to full-time or part-time engagements. Flexible with time zones for long-term projects. If you’re looking for a senior .NET engineer who can handle both backend systems and Windows desktop applications with confidence, feel free to reach out.