I’m a senior software developer from Portugal with more than 20 years of experience building commercial desktop and mobile applications. I help teams build, stabilize, refactor, and extend products that involve real technical complexity. My work is focused on desktop and mobile software where senior technical judgment matters: Qt/C++ applications, native iOS and Android apps, performance-sensitive features, media and audio/video pipelines, computer vision, hardware integration, OS-level behavior, and long-term maintainability. I have worked on commercial products used by real customers, including projects such as Rocketbook - Document Scanning, Triller - Music Video Social Network, ROVR Radio - Audio Production & Dashboard, Toby - AI Real-Time Audio Translation, iContact - Camera Widget, VideoShop - Video Composition, iGreet - Augmented Reality Greeting Cards, LeanStreamer - Multiple Audio Encoding Streaming Tool, BigRoom - Automated AI Editor, and other desktop and mobile applications that required reliable implementation and careful technical decision-making. Clients usually hire me when they need help with: • building a desktop or mobile product properly from the ground up • refactoring an existing codebase without unnecessary rewrite risk • solving platform-specific issues that are blocking progress or release • implementing complex native features involving camera, audio, video, files, hardware, or OS APIs • improving architecture, maintainability, performance, and stability • adding senior technical depth to an existing team or codebase My core expertise includes Qt/C++, desktop software, native iOS and Android development, software architecture, refactoring, performance optimization, media processing, computer vision, and hardware or platform-level integration. I’m especially well suited for products that already exist and now need to be improved carefully. That may mean stabilizing a codebase, modernizing architecture, solving difficult technical issues, or extending the product in a way that remains clean and maintainable. I care about building the right foundation early, keeping the codebase understandable, and making technical decisions that still make sense in the long run. If your product already exists and needs senior technical help to move forward safely, I’d be glad to discuss it.

With 𝟭𝟰+ 𝘆𝗲𝗮𝗿𝘀 architecting in the .NET ecosystem, I design C# .NET and cloud-native architectures that are built for the 𝟮𝟬𝟮𝟲 reality: scalable across AWS and Azure, secure by default, and wired for AI from day one. Whether you're a founder launching your first SaaS or a CTO staring down a legacy monolith that nobody wants to touch, I bring the technical leadership to turn that vision into something fast and maintainable. What I Actually Bring to the Table: - Legacy Modernization: I've untangled enough "spaghetti" .NET Framework (3.5/4.8) codebases to know that rewriting isn't always the answer.. but when it is, I migrate into clean, modular .NET 8/9 microservices that your team can actually work with. - AI & Automation: From Azure OpenAI to AWS Bedrock, I implement agentic workflows and RAG pipelines that automate the boring stuff and let your team focus on what matters. - Performance Engineering: SQL Server query plans, indexing strategies, cloud cost optimization, I've cut latency and slashed AWS/Azure bills by 30%+ more times than I can count. - Security-First Architecture: Zero-Trust, OAuth2, SOC2-compliant designs for fintech, healthcare, and anyone who can't afford a breach headline. The 𝟮𝟬𝟮𝟲 Stack I Work In: Backend: C#, ASP.NET Core 8/9, MVC, Web API, gRPC, SignalR, Blazor (Server/WASM) Frontend: Angular 19, React (Next.js), TypeScript, Tailwind CSS Cloud & DevOps: Azure (Functions, Logic Apps, Service Bus, OpenAI) · AWS (Lambda, S3, Bedrock) · Docker · Terraform · GitHub Actions · CI/CD · Microservices Architecture · Domain-Driven Design · CQRS · OAuth2 · JWT Data: SQL Server (optimization specialist), PostgreSQL, MongoDB, Vector Databases for AI/RAG pipelines Why 𝟭𝗖𝟰+ Years Matters: I've led teams, rescued failing projects, and shipped for startups and Fortune 500s alike. I speak ROI and Go-To-Market as fluently as I speak CI/CD. You'll not be hiring someone who just writes code, you'll get a technical partner who makes sure your technology accelerates your business instead of holding it back. Available for architectural audits, project rescues, or long-term development. Click 'Message' let's talk about where your project needs to go.

I am a software developer with 13+ years of experience in building high-performance, cross-platform desktop applications using Qt/C++ and PyQt. I specialize in desktop software for video streaming, computer vision, and AI-powered solutions, delivering efficient, scalable, and user-friendly applications for Windows, Linux, and macOS. My expertise includes: Desktop Application Development: Qt, PyQt, cross-platform UI/UX, backend logic, networking Computer Vision & AI: OpenCV, TensorFlow, Keras, real-time object detection, face recognition Video Streaming & Processing: FFMPEG, OpenRTSP, live camera streaming, playback, recording WebRTC & Web Integration: Real-time audio/video apps, chat, and web interfaces Database & Backend: MySQL, PHP, server-side scripting, automation I focus on delivering high-quality solutions that solve real-world problems, optimize performance, and provide seamless user experiences. I am available for short-term projects, long-term contracts, and ongoing support.

💻 Back-End Development ⚡️ Full Stack Development ⚡️ Desktop Software Development 📜 .NET and C#: 🔹 ASP.NET Core 🔹 Entity Framework Core 🔹 FluentValidation 🔹 MediatR 🔹 Automapper 🔹 FastExpressions 🔹 Serilog 🔹 SignalR 🔹 Identity Framework Core 🔹 BenchmarkDotNet 🔹 xUnit, nUnit, FluentAssertions, NSubstitude, Bogus 🔹 Polly 📜 Databases: 🔹 MS SQL 🔹 MySQL 🔹 Postgres 🔹 MongoDB 📜 Architecture: 🔹 DDD 🔹 Event Driven Design 🔹 Clear Architecture 💻 Front-End Development ⚡️ Mobile App Development ⚡️ Full Stack Development 🚀 Expertise in: 📱 React & React Native (Expo): Building dynamic web and mobile applications 🌐 Modern Frontend Frameworks: Proficient in React, Angular 2+, Vue.js, and Next.js for responsive, scalable web development 🔧 Backend Knowledge: Familiar with PHP (Laravel, Slim, Lumen) and Node.js for basic backend integration 🛒 CMS & E-Commerce: Expertise in WordPress, WooCommerce, Plentymarkets, Magento theme/plugin development, and custom integrations ✨ Clean, Efficient Code: Passionate about writing maintainable and scalable solutions for a smooth user experience 🔗 API Integration: Skilled in SOAP/RESTful API development and integration for seamless client connectivity 💪🏻The following stack that successfully used: 🔹SCSS 🔹CSS 🔹HTML 🔹TypeScript 🔹RXJS 🔹NGRX 🔹NextJS 🔹ReactJS 🔹REDUX 🔹SAGA 🔹Promises 🔹Server Side Rendering based on NextJS 🔹NestJS 🔹MySQL 🔹ExpressJS 🧠 AI: 🔹 Machine Learning 🔹 Large Language Models (LLM) 🔹 Prompt Engineering 🔹 LangChain 🔹 OpenAI 🔹 Anthropic 🔹 Google GenAI 🔹 FAISS 🔹 Retrieval Augmented Generation (RAG) 𝙎𝙚𝙖𝙧𝙘𝙝 𝙛𝙤𝙧 𝙢𝙚 𝙪𝙨𝙞𝙣𝙜 𝙩𝙝𝙚𝙨𝙚 𝙠𝙚𝙮𝙬𝙤𝙧𝙙𝙨: C#, ASP.NET Core, .NET Framework, Entity Framework, SQL Server, PostgreSQL, MySQL, REST APIs, JSON, XML, GraphQL, Razor, Blazor, Php, Python, Angular, React, Vue.js, JavaScript, TypeScript, HTML5, CSS3, SCSS, Bootstrap, Tailwind, Azure (App Services, Functions, DevOps, Blob Storage), AWS, Docker, Kubernetes, Microservices, CI/CD, Git, GitHub, GitLab, TDD, xUnit, NUnit, Dapper, Swagger, OAuth, JWT, WebSockets, RabbitMQ, Redis, SignalR, Sitecore, Umbraco, Kentico, DNN, Orchard Core, Contentful, Strapi, ADO.NET, ASP.NET MVC, AngularJS, AJAX, Adobe Photoshop, ASP.NET Web API, Google Analytics, Google Chrome Extension, Ecommerce Website, Browser Extension, Web Application, Website Redesign, API, API Integration, Desktop Application, Website Optimization, Software Debugging, Web Development, Database Development, AI Agent Development, WildFly, Apache HTTP Server, Eclipse Jetty, Microsoft IIS, IBM WebSphere, SQLite, Mimer SQL, Azure Cosmos DB, MongoDB, EC2, ECS, Lambda, S3, RDS, CloudFormation, AWS Backup, IAM, CloudFront, CloudWatch

Software developer with 10+ years of experience (C#/.NET, Golang, Python). Looking for complex and long-term projects, both interested in cross-platform development and Windows development. Also, I have experience with AI and computer vision projects. If you've got a project or a project idea, please contact me and we will discuss it.

- 100% job success - 5-star ⭐ rating on all jobs - Client satisfaction 😇 is my top priority I'm a Software Engineer with 3 years of experience in C++ and the Qt framework, specialising in developing high-performance applications and intuitive GUIs. - Proficient in C++ and Qt framework - Expertise in GUI design and implementation - Strong problem-solving and debugging skills - Focused on delivering quality and scalable solutions

🟢 𝐀𝐕𝐀𝐈𝐋𝐀𝐁𝐋𝐄 NOW 👋 Hi there, I'm Artem! Need a developer to build a SaaS, MVP, or support a legacy system? I'm your full stack developer expert. With 15+ years as a Senior .NET Full Stack Developer, I plan, architect, and deliver high-performance applications that scale. Through my agency CodeLuxSolution and direct Upwork engagements, I've completed 66+ projects globally, transforming outdated systems into modern, blazor-powered solutions that drive user adoption and slash operational costs. ═══════════════════════════════════════════════════════════ 🏆 Why Our ASP.NET Core and .NET Developer Solutions Stand Out ⭐ 15+ years as a Senior .NET Full Stack Developer and Desktop Application specialist ⭐ 66+ custom projects delivered: 36 on Upwork, 30+ through enterprise contracts ⭐ Top Rated on Upwork with 100% Job Success Score ⭐ Leading projects for USA educational platforms serving 250k+ users after regulatory updates ⭐ Enterprise SaaS platforms in management and analytics spanning 20+ person teams ⭐ Desktop application migrations from WinForms to Blazor Server reducing deployment cycles to 1 second ⭐ ASP.NET WebForms to .NET Core migrations accelerating page load times by 100x (30s down to 0.5s) ⭐ High-load IoT systems optimized from 3 servers down to 1 server, cutting infrastructure costs 66% ⭐ ASP.NET MVC to RazorPages performance gains delivering 3x faster rendering ⭐ Blazor developer expertise enabling remote-first access and real-time data sync across 1000+ concurrent users ⭐ .NET Core microservices reducing deployment risk from multi-day windows to single-second updates ═══════════════════════════════════════════════════════════ 🚀 Services | ASP.NET Core and .NET Developer Expertise ▶ Enterprise SaaS Architecture - Scalable, Management and Analytics Focused ► ASP.NET Core microservices for high-load systems processing thousands of IoT requests per second ► .NET Core backend serving 250k+ users on educational platforms with zero downtime ► Blazor Server and Blazor WASM applications enabling remote access and cross-user data synchronization ► SQL Server optimization and EF Core entity mapping for complex domain logic ► Developer-led database scaling strategies reducing server footprint by 66% ▶ Legacy System Modernization - WebForms to Modern .NET ► ASP.NET WebForms to .NET Core rewrites accelerating page loads from 30s to 0.5s ► WinForms Desktop Application refactoring into Blazor Server reducing update cycles to 1 second ► ASP.NET MVC to RazorPages migration delivering 3x performance improvement ► Eliminate version conflicts across 1000+ users with web-based Blazor deployment ► .NET Framework to .NET Core infrastructure consolidation cutting infrastructure needs from 3 servers to 1 ▶ Custom Desktop Applications - WinForms and Windows Services ► WinForms application development for enterprise productivity tools ► Windows Services for background processing and system integration ► Desktop application architecture supporting offline and connected scenarios ▶ SaaS Platform Development - Full Stack from Concept to Scale ► ASP.NET Core APIs powering management and analytics SaaS dashboards ► Blazor components for real-time reporting and user collaboration ► .NET developer expertise in multi-tenant architecture and data isolation ► High-performance SaaS solutions serving thousands of concurrent users ▶ Specialized Modernization Services ► WinForms to Blazor Server conversion enabling work-from-anywhere deployment ► ASP.NET WebForms to .NET Core rewrites for systems handling high-load IoT data ► MetaTrader indicator development and NinjaTrader platform expertise ► Educational platform scaling from pilot to 250k+ user systems ► Fire safety and emergency management SaaS currently in development ═══════════════════════════════════════════════════════════ ⚙️ Workflow, Tech-Stack and Extra Value 🔍 Discovery and Requirements Analysis ► Understanding legacy system pain points and defining success metrics for migration projects ► Competitive analysis and user experience mapping for SaaS platforms 🏗️ Architecture and Design ► Mapping WinForms components to Blazor Server architecture ► Designing ASP.NET Core microservices for SaaS platforms ► Planning infrastructure consolidation strategies for high-load systems ► .NET developer best practices for scalability and maintainability 💻 Development and Integration ► C# as primary language chosen over Python for development velocity and C++ for performance parity ► ASP.NET Core | Blazor Server | Blazor WASM | RazorPages | .NET Framework legacy ► HTML5 | CSS | JavaScript | SQL Server | EF Core with advanced querying ► WinForms for Desktop applications | Windows Services | API development ► Integration with existing enterprise systems and third-party APIs ⚡ Performance Optimization ► ASP.NET WebForms to .NET Core refactoring reducing page loa

Senior Software Architect specializing in secure systems and IoT Sec solutions with 15+ years of experience. I architect and deliver end-to-end nfc solutions, from embedded firmware to cloud-based backend systems. 🎯 CORE EXPERTISE IOT Systems - NFC Solutions: Reader/Writer, HCE, Digital Wallets (Android/iOS) - Smart Cards: JavaCard, MIFARE, DESFire, NTAG,Global Platform,GP,JCOP,Secure Element - Security: PKI, FIDO, Secure Element,HSM, PCI-DSS Compliance - RFID Systems: Asset Tracking, Access Control - EMV Payment: L1/L2/L3 Kernel Development & Certification - Microcontrollers: ESP32, STM32 (WiFi/BLE, RTOS) - Firmware: Secure Bootloader, OTA Updates, Real-time Systems - Industrial Applications: POS Terminals, Vending Machines, Access Control - IoT Architecture: Sensor Integration, Remote Management Full-Stack Development - Backend: Node.js, REST APIs, Database Design (SQL/NoSQL) - Cloud Services: Firebase, AWS/Azure/GCP Deployment - Mobile: Android (NFC APIs), iOS (CoreNFC), React Native - Desktop: Qt, .NET, Cross-platform Applications - Languages: C/C++, JavaScript/TypeScript, Java, C# 💼 SIGNATURE PROJECTS ✅ ESP32 IoT Systems - Created NFC-enabled payment solution with cloud integration - Built secure firmware with OTA update capabilities - Integrated Firebase for real-time data synchronization ✅ Cross-Platform Digital Wallet - Developed mobile wallet supporting EMV contactless payments - Implemented HCE and Secure Element integration - Built Node.js backend with Firebase authentication ✅ Enterprise RFID Solutions - Designed asset tracking systems for industrial clients - Implemented access control with NFC/RFID readers - Deployed cloud-based management platform ✅ EMV Payment Terminal Solutions - Developed EMV L2 & L3 kernel for contact/contactless terminals - Achieved EMVCo certification for payment applications - Implemented secure key management and transaction processing 🔧 TECHNICAL STACK Hardware: ESP32, STM32, NFC Readers, RFID Systems Backend: Node.js, Express, Firebase, REST APIs Database: MongoDB, PostgreSQL, MySQL, Firestore Cloud: Firebase, AWS, Azure, Docker deployment Mobile: Android, iOS, React Native Desktop: Qt, .NET, Windows/Linux Security: PKI, FIDO, PCI-DSS, Secure Boot 📋 CERTIFICATIONS & STANDARDS EMVCo, PCI-DSS, PBOC, Global Platform, ISO 14443 I deliver production-ready solutions with clean code, comprehensive documentation, and ongoing support. Available for both fixed-price projects and long-term contracts.

Hello, Thank for visiting my profile. I'm a software engineer with 8 years of experience in developing Desktop Application. I have worked on many projects in this field and got success. I am good at C/C++, Win32, MFC, Qt, C# WPF, Winform, python, Java core and proficient in Visual Studio, Eclipse, Qt Creator. I deeply understand OOP design and GoF design patterns. I am familiar with both Window and Linux. I very happy to cooperate with you. Hai Nguyen.

I am a senior software engineer with strong experience across system-level and application-level development. I work with C#, C++, Python, and .NET, building high-performance backend systems and clean desktop or embedded firmware, mobile applications. I have solid experience with WPF for desktop apps, and also iOS and macOS development when product needs cross-platform support. Main Tech Skills: ⭐ Languages: C#, C++, Python, Swift, Objective-C, Bash, PowerShell ⭐ Frameworks & Platforms: .NET Core, ASP.NET, Entity Framework, Dapper, WPF, WinForms, Xamarin, MAUI, iOS, macOS ⭐ Systems & Low-Level: Linux, Linux Kernel, POSIX, Multithreading, Concurrency, Parallel Programming, Memory Management, Pointers, IPC, Signals, Socket Programming, Low-Level Debugging, System Calls ⭐ Backend & APIs: REST APIs, gRPC, WebSockets, Microservices Architecture, System Design, Distributed Systems, API Security, OAuth2, JWT, Rate Limiting ⭐ Databases & Caching: PostgreSQL, MySQL, MongoDB, SQLite, Redis, Indexing, Query Optimization ⭐ DevOps & Cloud: Docker, Kubernetes, CI/CD, GitHub Actions, Azure DevOps, AWS, Nginx, Linux Server Management ⭐ Tools & Engineering: Git, CMake, MSBuild, Makefile, Visual Studio, VS Code, CLion, Xcode ⭐ Testing & Quality: Unit Testing, Integration Testing, Test Automation, TDD, Debugging, Profiling, Static Analysis ⭐ Architecture & Patterns: Clean Architecture, SOLID Principles, Design Patterns, Domain-Driven Design, Event-Driven Architecture ⭐ Security: Secure Coding, Authentication Systems, Encryption Basics, Data Protection ⭐ Other: Performance Optimization, Reverse Engineering, Code Refactoring, System Optimization, Network Programming, Data Structures, Algorithms, Logging, Monitoring A big part of my work is close to the system. I have experience working with Linux environments, including kernel-level understanding, low-level debugging, and performance tuning. I am comfortable solving problems not only in code, but also in system behavior, concurrency, and integration between components. I don’t just write code. I focus on stability, performance, and long-term maintainability. I often work on fixing complex issues, optimizing slow systems, or rebuilding parts that were not designed well from the beginning. Outside of work, I value a calm and stable life. I spend time with my family, and this helps me stay focused and consistent in my work. I prefer long-term cooperation where both sides trust each other and build something meaningful step by step. I can work independently, read existing codebases quickly, and deliver clean solutions without overcomplicating things. I am also comfortable joining ongoing projects and improving them step by step. If you need someone who understands both high-level architecture and low-level details, I can help. Thanks.