Senior .NET Full-Stack Developer with 8+ years of experience building SaaS platforms, ERP systems, REST APIs, AI-powered applications, and enterprise software used by thousands of users. I help businesses launch scalable, secure, and cloud-ready solutions using ASP.NET Core, C#, Azure, React, Angular, and modern AI technologies. My expertise spans ASP.NET Core, .NET 8/9, C#, microservices, cloud infrastructure, enterprise integrations, and modern frontend frameworks including React, Angular, Blazor, and Next.js. I have successfully delivered scalable applications ranging from fintech and logistics platforms to healthcare, eCommerce, AI-powered SaaS products, and enterprise workflow systems. In addition to backend and frontend engineering, I have strong experience integrating AI-powered solutions into enterprise applications, including intelligent chatbots, recommendation engines, predictive analytics, workflow automation, computer vision, and AI-assisted decision systems. I have worked with AI integrations, automation frameworks, and cloud AI services to improve operational efficiency and user engagement. Languages C#, ASP.NET Core, .NET Framework, .NET 8/9, TypeScript, JavaScript (ES6+), SQL, T-SQL, Python, HTML5, CSS3, Dart, JSON Frontend Technologies React.js, Next.js, Angular, Blazor, Razor Pages, MVC, Bootstrap, Tailwind CSS, Material UI, Shadcn/UI, jQuery Backend & Frameworks ASP.NET Core MVC, ASP.NET Web API, Entity Framework Core, LINQ, SignalR, MediatR, Dapper, Minimal APIs, gRPC, MassTransit, RabbitMQ, Hangfire, Quartz.NET, Node.js, Express.js, NestJS Cloud, DevOps & Infrastructure Microsoft Azure, Azure DevOps, AWS Services, Docker, Kubernetes, GitHub Actions, Firebase, Cloud Functions, IIS, Nginx, CDN & Security Platforms Databases & Storage Microsoft SQL Server, PostgreSQL, MySQL, MongoDB, Redis, DynamoDB, SQLite, Firebase Firestore, Elasticsearch, Cloud Storage Solutions Integrations & APIs Payment Gateways, Logistics APIs, Shipping Integrations, GPS & Fleet Tracking Systems, ERP/CRM Integrations, Marketplace APIs, Communication Platforms, AI Services, Authentication Providers, Real-time Notification Systems Tools & Platforms Visual Studio, VS Code, Git, GitHub, Bitbucket, Jira, Postman, Swagger/OpenAPI, Docker Desktop, Azure Portal, Firebase Console Architecture & Methodologies Microservices Architecture, Clean Architecture, Domain-Driven Design (DDD), CQRS, Event-Driven Architecture, SOLID Principles, MVC, MVVM, Agile, Scrum, Kanban Core Expertise • Enterprise SaaS Platforms • Fintech & Payment Applications • Logistics & Transportation Management Systems • Fleet Management & Real-time Tracking • eCommerce & Marketplace Solutions • Healthcare & Telemedicine Platforms • AI-Powered Applications • CRM / ERP Systems • Booking & On-demand Platforms • IoT & Device Integrations • Warehouse & Inventory Management • Multi-tenant Applications • Secure API Development • Cloud-native Applications • Real-time Applications & Notifications AI development: • OpenAI API • GPT-4o • RAG • Vector Databases • AI Agents • LangChain • MCP • Cursor AI • Workflow Automation • AI Chatbots

I help SaaS companies, startups and engineering teams by creating clear, practical documentation that makes products easier to use and maintain. My work includes user guides, how-to guides, API documentation, SOPs, and developer documentation. I always focus on creating content that helps users complete tasks quickly, reduces repetitive support requests and improves onboarding for both customers and internal teams. With a strong background in software engineering and web development, I understand the systems behind the documentation. This allows me to work directly with APIs, codebases, product teams and technical stakeholders to create accurate, well-structured documentation that stays useful as products evolve. 🔹 User Guides | How-to Guides I create clear, task-focused documentation that helps users understand your product, complete workflows efficiently, and reduce dependency on support teams. ✅ User guides ✅ How-to guides ✅ Step-by-step tutorials ✅ Product onboarding guides ✅ Feature walkthroughs ✅ Knowledge base articles ✅ FAQs and troubleshooting guides ✅ Internal process documentation ✅ User manuals ✅ Visual workflows and screenshots 🔹 API Documentation (OpenAPI / Swagger Expert) I create complete, production-ready API documentation that includes: ✅ Clear endpoint descriptions ✅ Request body parameters ✅ Query parameters & path parameters ✅ Authentication flows (JWT, OAuth, API Keys) ✅ Response structures with status codes ✅ Error codes with detailed schemas ✅ Properly defined data models ✅ Example requests & responses ✅ Postman collections ✅ SDK usage examples I work extensively with: Markdown • YAML • JSON • OpenAPI • Swagger • Redocly • Postman • GitHub ▪︎ ReadMe • Google Docs ▪︎ Zendesk • Docusaurus Your APIs will not only function well - they will be understood instantly. 🔹 Developer & Technical Documentation I create: ✅ Developer Guides ✅ API References ✅ SDK Documentation ✅ Integration Guides ✅ Database Documentation (SQL & NoSQL) ✅ System Architecture Documentation ✅ Technical Blogs & Articles ✅ Internal Engineering Documentation ✅ System Operating Procedures (SOPs) ✅ User Manuals ✅ How-To Guides ✅ Step-by-Step Tutorials Whether your audience is developers, internal teams or non-technical users - I adapt tone, depth and structure accordingly. 🔹 Developer Portals & Documentation Platforms I build structured, branded documentation portals using: ✅ Redocly ✅ ReadMe ✅ GitBook ✅ Docusaurus ✅ Mintlify ✅ Stoplight ✅ Confluence ✅ GitHub I ensure your documentation is searchable, scalable, version-controlled, and beautifully structured. 🔹 Technical & Engineering Strength My technical capabilities allow me to go beyond surface-level writing: ✅ Testing and validating APIs with Postman ✅ Running and testing SDKs ✅ Code commenting and codebase documentation ✅ JavaScript & TypeScript documentation ✅ Python code refactoring & documentation ✅ REST API workflows ✅ JSON, YAML, HTML, CSS ✅ Database structure documentation (SQL | NoSQL) Because I understand the code, I document it accurately. 🔹 What You Can Expect ✅ Clear, concise, and developer-friendly API documentation ✅ Reduced support tickets and improved onboarding ✅ Well-structured, scalable documentation systems ✅ Fast turnaround & deadline commitment ✅ Proactive communication ✅ Long-term documentation management support #TechnicalWriting #TechnicalDocumentation #UserDocumentation #UserGuides #APIDocumentation #OpenAPI #Swagger #SOPWriting #KnowledgeBase #DeveloperDocumentation #InstructionManual #ProcessDocumentation #SoftwareDocumentation #Markdown #GitBook

🚀 Top Rated Plus | Full Stack, Embedded & AI Experts | 11+ Years of Proven Success | 100+ Projects Delivered We help startups and businesses turn complex ideas into powerful, scalable digital products. With 11+ years of experience, 5500+ Upwork hours, and 100+ successfully delivered projects, our team specializes in building modern web platforms, AI-powered systems, and embedded solutions used across multiple industries. ⭐ 100% Job Success Score 🔁 90% Repeat Clients 💬 Fluent English & Clear Communication ⚡ Fast Delivery & Long-Term Support Our focus is simple: build reliable, scalable, and high-performance solutions that create real business value. 💻 What We Do Best 🌐 Full Stack Development 🌍 Industries We Work With-- We’ve successfully delivered solutions in: 🏥 Healthcare 💳 Fintech 🏭 Manufacturing 🍔 Food Industry 💎 Laser & Diamond Technology 🚗 Automotive 📊 Enterprise Platforms 🤝 Why Clients Choose Us ✔ 11+ Years Development Experience ✔ High-Quality & Scalable Code ✔ Clear Communication & Transparency ✔ Long-Term Technical Partner ✔ Reliable Delivery We design and develop high-performance web applications, SaaS platforms, and custom software. Tech Stack-- React.js, Next.js, Vue.js Node.js, NestJS PHP, Laravel, CodeIgniter, CakePHP TypeScript, JavaScript, Python HTML5, CSS3, Tailwind, Bootstrap ✔ SaaS Platforms ✔ Dashboards & Admin Panels ✔ Custom Business Platforms ✔ Scalable Backend Systems 🔌 API Development & Integrations We create secure backend systems and complex integrations. Integrations REST & SOAP APIs WebSockets, MQTT, WebRTC Firebase Alexa Skills Payment Systems Stripe PayPal Razorpay Custom payment workflows 🤖 Artificial Intelligence & Machine Learning We build AI-driven applications that automate processes and unlock data insights. AI Expertise LLM Applications (OpenAI, Claude, DeepSeek) Retrieval Augmented Generation (RAG) NLP & Document Intelligence Predictive Analytics Intelligent Automation AI Solutions ✔ AI Chatbots & Assistants ✔ AI Search Platforms ✔ Document Processing Systems ✔ Data Analysis & Insights 👁️ Vision AI & Speech AI Computer Vision OCR & Document Scanning Object Detection Image Analysis Speech AI Speech-to-Text (STT) Text-to-Speech (TTS) Voice Biometrics 🧠 Embedded Systems & Hardware Development We build intelligent hardware-software solutions for IoT and industrial systems. Technologies C / C++ / Embedded Linux Qt / QML Raspberry Pi Arduino ESP32 / ESP8266 ARM / FPGA Protocols SPI • UART • RS485 • Gigabit Ethernet • XY2-100 Applications include CNC controllers, automation systems, computer vision devices, and real-time processing systems. ☁️ Cloud & DevOps We build cloud-native, scalable infrastructure. Platforms AWS (Lambda, S3, CloudFront, Step Functions) SageMaker, Bedrock AWS IoT Core Google Cloud Digital Ocean DevOps Docker Jenkins CI/CD Pipelines GitOps 🧰 Tools & Development Workflow We follow Agile development with full transparency. Project Tools Jira • ClickUp • Trello • Asana • Slack • Basecamp Version Control GitHub • GitLab • Bitbucket Engineering Practices Agile / Scrum • Unit Testing • UML Architecture We don’t just build software- we build solutions that help businesses grow. 📩 Have a project in mind? Send us a message - we’d love to discuss it.

I'm the CEO of NUS Technology, a software team of 75+ engineers based in Vietnam, working with international clients since 2013. Unlike typical dev shops that deliver isolated features, we design and build the core systems that power day-to-day operations: internal platforms, integrations, and automation workflows, and we stay accountable for outcomes, not just output. Over the past 12+ years we've worked closely with founders and operators (especially in Australia, the US, and Europe) on products where performance, maintainability, and business alignment truly matter. WHY CLIENTS CHOOSE US - Top Rated Agency on Upwork, 98%+ Job Success Score since 2013, 4.8/5.0 average rating - $10M+ in project value delivered - Long-term partnerships: many clients have worked with us for 5-10+ years - 75+ co-located engineers: 60+ web developers, 15+ mobile developers, plus QA, BAs, PMs, and designers WHAT WE DO BEST Operations platforms (our core) We design the central system that orchestrates bookings, payments, teams, hardware, and compliance into one seamless operation: software that bends to your process, not the other way around. We handle the integrations Zapier can't and SaaS avoids: deep data synchronization, legacy platforms, and compliance-grade audit trails where failure isn't an option. Web development - Ruby on Rails (deep expertise): production-grade apps, clean architecture, performance optimization, complex domains and high-traffic systems - Frontend: React, Next.js, Vue.js, TypeScript, Tailwind CSS - Node.js, PHP (Laravel, Symfony, WordPress), Python (Django, Flask) - RESTful and GraphQL APIs Mobile development - Native (Swift, Kotlin) and cross-platform (React Native, Flutter) for iOS and Android Cloud & DevOps - Scalable infrastructure on AWS (EC2, RDS, S3, Lambda, CloudFront), Google Cloud, Heroku - CI/CD (GitHub Actions, GitLab CI, CircleCI), Docker, monitoring and performance tuning - Cost-efficiency and scalability built in from early stages eCommerce - Shopify (custom themes, public/private apps, API integrations, migrations) - Spree Commerce, Saleor, and custom platforms when off-the-shelf doesn't fit HOW WE WORK - Outcome-driven: we focus on business results, not just shipping code - Ownership mindset: we act like a technical co-founder, not a contractor - Proactive: we surface technical debt and scaling bottlenecks before they escalate - Clear communication across time zones (we're GMT+7, with strong overlap for AU and partial US/EU) - Long-term thinking: we build systems that scale, not quick hacks that break later HOW YOU CAN WORK WITH US 1. Operations platform development: internal platforms, SaaS, workflow automation, complex integrations, replacing fragmented tools with a unified system 2. Dedicated engineering teams: backend, frontend, mobile, and QA engineers as an extended team, often for multiple years 3. Product development & MVPs: from idea to launch, fast but not fragile If you're looking for a team that thinks beyond code, challenges assumptions, and builds something that actually lasts, let's talk.

I can solve any custom API integration issue that other developers have given up on - from phone door openers to Swiss and American banks, from 1974's nacha technologies to artificial intelligence, crypto and blockchain. I have 22+ years of overall 🌐 Web Development experience, including 18+ years with ⚙️ Custom PHP, 16+ years with 📝 WordPress and 🛠️ API Integration, and 12+ years with 🛍️ eCommerce, along with other related technologies and programming languages. Located in Washington State, I have no problem working 30-40+ hours during American time. I am self-controlled, self-organized, flexible and learnable, I can adapt to whatever your project requires. ================================ 🛠️ API INTEGRATION I offer custom API integration for a wide range of services using the most common REST, SOAP and GraphQL protocols. There is a strong focus on authentication, error handling and personal data security. I have extensive experience working with 1,200,000+ records at a time with regular automatic updates down to the minute. 🛠️ API integration development 🛠️ Data transformation and processing 🛠️ Analytics, reporting and visualization 🛠️ Custom API/feeds development Some API integrations I have experience with: Ahrefs API, Amazon API Gateway, Amazon AWS API, Amazon Lambda API, Amazon PA API, Amazon S3 API, Bank Of America API, Barcode Lookup API, BigCommerce API, BlueBanc API, Brevo API, Bright Data API, ChatGPT API, Cloudflare API, CoinBase API, Detroit Trading API, Dukascopy API, Dynadot API, eBay Product API, Envato API, Ethereum API, Etherscan API, First Data API, Fiserv API, GoDaddy API, Google Places API, HubSpot API, Jobber API, Lead Byte API, Lead Galore API, Lead Horizon API, Lead Prosper API, Leads Hook API, MaxMind API, Meta Marketing API, Modern Dropship API, NameSilo API, NowPayments API, OpenAI API, PayPal API, Plaid API, Polygon API, Polygon Scan API, Quin Stage API, Quin Street API, Relograde API, RiskPay API, Round Sky API, Samsara API, Seamless Chex API, SendGrid API, Shopify API, Slack API, Square API, Stripe API, Supabase API, Tatum API, Thumbtack API, Trulia API, Twilio API, VideoHive API, WhatsApp Cloud API, WooCommerce API, WordPress API, Zillow API, etc... ================================ 🧠 DATA PROCESSING I offer ETL (Extract, Transform, Load) data processing services that include cleaning, transforming, and analyzing data to extract valuable insights. This can involve working with external APIs, large datasets, cloud or database storage. I have extensive experience with tools like PHP, databases and cloud services for efficient processing. 🧠 Data cleaning and transformation 🧠 Real-time data analysis and reporting 🧠 Data files creating and processing 🧠 Artificial intelligence enhancing ================================ ⚙️ MICROSERVICES I offer development of microservices for external project management or communication between different projects. This includes receiving data via API, converting it to the required format, storing it in a database or sending it via API to another service. I have experience working with Amazon, Google, Meta as well as smaller private services. ⚙️ Inbound and outbound API integration ⚙️ Converting one type of API to another type ⚙️ Splitting large queries into multiple queries ⚙️ Automatic processing of requests on schedule ================================ 🛍️ ECOMMERCE I offer product import/export and inventory management for eCommerce stores. This includes working with popular WordPress, Shopify, WooCommerce and BigCommerce as well as external marketplaces such as Amazon, eBay, Google Shopping, etc. I have extensive experience working with 100,000+ inventory processing and synchronization. 🛍️ Inventory management solutions 🛍️ Sales and performance analytics 🛍️ Fraud detection and prevention 🛍️ Marketplaces synchronization ================================ One last thing... there's a reason I have a 100% success score on Upwork. That's because I get it right the first time, or I will work for free until you're happy. Thank you for taking the time to review my profile. Looking forward to connecting with you!

US based digital nomad helping businesses and people where I can. I specialize in React, Python and Databricks Solutions. Rates may vary

Are you looking for a senior Next.js developer who can architect a high-performance, SEO-optimized AI web application or SaaS MVP — and ship it on time? I'm MD Saidul Islam, a Full-Stack Software Engineer with 5+ years of experience building production-grade web products using TypeScript, Next.js, and Node.js. I turn complex business requirements into scalable, secure, and pixel-perfect digital products. What I specialize in: SaaS MVP Development — Rapid prototyping and deployment using Next.js, Tailwind CSS, and Supabase, with full CI/CD pipelines on Vercel. AI-Powered Web Applications — Custom OpenAI integrations, intelligent chat interfaces, and smart automation workflows built to scale. Figma to Next.js Conversion — Pixel-perfect, mobile-first UIs that match your design system exactly. SEO & Core Web Vitals Optimization — Server-side rendering (SSR), structured data markup, and sub-second page loads that rank. Admin Dashboards & CRM Platforms — Role-based access control, dynamic data visualization, and secure REST APIs. Tech stack: Frontend: React.js, Next.js (SSR, SSG, ISR), TypeScript, Tailwind CSS, HTML5/CSS3 Backend: Node.js, Express.js, RESTful APIs, JWT Authentication Database: MySQL, Supabase, Prisma ORM AI & Automation: OpenAI API, custom AI chatbots, intelligent workflow design DevOps: Vercel, Netlify, GitHub Actions, CI/CD Why clients hire me over other developers: ✔ SEO-first architecture — every project is built with server-side rendering from day one, maximizing organic search visibility. ✔ Performance-focused — I target Core Web Vitals scores that put you ahead of 90% of competitors. ✔ Clean, maintainable code — documented, modular, and built to hand off without friction. ✔ Clear communication — weekly updates, fast response times, and proactive problem identification before they become blockers. If you have a product idea, a Figma file, or a performance problem — let's talk. I'm ready to review your project scope and get started.

I specialize in back-end web development, focusing on leveraging technologies like Laravel and Symfony to create robust web applications. My skill set includes: ✅Proficiency across a range of technologies including PHP 5.6 / 7.1 / 7.2, Laravel 5.x, LAMP, AWS, JavaScript, WordPress (theme and plug-in development), Opencart CMS, Git, MySQL, and MongoDB. ✅Extensive hands-on experience in crafting efficient back-end solutions using Laravel and Symfony, ensuring optimal performance and scalability. ✅Expertise in integrating various technologies and platforms to create seamless and dynamic web applications that meet client specifications. ✅Proven ability to collaborate effectively with cross-functional teams, ensuring a cohesive and streamlined development process. My main goal is my clients' benefit. Don't hesitate, contact me and lets develop your web app! 𝐊𝐞𝐲𝐰𝐨𝐫𝐝𝐬 𝐟𝐨𝐫 𝐭𝐡𝐞 𝐩𝐫𝐨𝐟𝐢𝐥𝐞: Back-End Developer, Back-End Development, PHP Frameworks, PHP Web Developer, PHP programming, Symfony Developer, Symfony 1.X, Symfony 2.X, Symfony 3.X, Symfony 4.X, Symfony 5.X, Symfony 6.X Sylius ,Laravel 4, Laravel 5, Laravel 6, Laravel 7, Laravel 8, Laravel 9, API’s, Custom PHP, JavaScript, API Integration, Web Development, HTML, HTML5, MySQL, Bootstrap, CSS. Laravel Engineer, Laravel Developer, PHP Laravel Expert, Senior Full Stack Laravel Developer, PostgreSQL, Docker, Gitlab, AWS, RESTful API, jQuery, AJAX, PHP Script, Database, Web Service, MySQL Programming.

PHP | React | REST API | WooCommerce Customization | Secure Code I solve the WordPress problems that page builders can't fix. If you are dealing with a broken API connection, a slow custom plugin, or a critical error that other developers couldn't diagnose, I can help. I am a Technical Developer who specializes in pure PHP/JS solutions, not just drag-and-drop design. My Core Specialties: Complex API Integrations: Syncing your WP site with Google APIs, CRMs, and external databases. Custom Plugin Development: Building lightweight functionality without bloat. Emergency Hardening: Fixing hacked sites and locking down REST API endpoints. Why 100% of my clients return: I don't guess. I debug. I write clean, documented code that won't break when you update WordPress next month. Let's fix your site correctly the first time.

🚀 Top-Rated Full-Stack & AI Developer | SaaS | LLM | Automation Expert With 10+ years of experience, I build scalable, high-performance web & mobile applications powered by modern full-stack technologies and advanced AI systems. I specialize in AI SaaS, LLM integrations, and automation platforms that don’t just work — they drive real business results. 🏆 Proven Track Record: ⭐200+ Projects Completed on Upwork ⭐100% Job Success Score ⭐80%+ Repeat Clients ⭐3300+ Hours Logged 💡 What I Can Build for You ✅ AI-powered SaaS platforms ✅ Smart chatbots & AI assistants (GPT, Claude, LLaMA) ✅ RAG systems with vector databases ✅ Workflow automation tools (n8n, APIs, agents) ✅ Full-stack web & mobile apps ✅ Custom dashboards, CRM, ERP systems 🤖 AI & LLM Expertise ✔LLM Integration: GPT-4/5, Claude, LLaMA, DeepSeek ✔RAG Systems: Pinecone, Weaviate, Milvus, ChromaDB ✔AI Use Cases: ✔Chatbots & AI agents ✔Document processing & summarization ✔AI automation & support systems ✔Predictive analytics & recommendations 💻 Full-Stack Development ⭐Frontend: 🔹React.js, Next.js, Angular, Tailwind CSS ⭐Backend: 🔹Node.js, NestJS, Laravel, Express ⭐Database & Cloud: 🔹MongoDB, PostgreSQL, MySQL 🔹AWS, GCP, Azure ⭐Mobile: 🔹React Native, Flutter ⚡ Why Clients Choose Me ✔ Clean, scalable, production-ready code ✔ Strong communication & fast response ✔ Business-focused solutions (not just coding) ✔ Reliable long-term collaboration ✔ Affordable, high-quality delivery 🚀 Let’s Build Something Powerful Whether you need an AI product, SaaS platform, or automation system, I can help you design, build, and scale it end-to-end. 💬 Send me a message — let’s turn your idea into a real product.