I'm a Full Stack Developer and .NET Developer with 10+ years building web applications that businesses actually run on. I take an idea and ship it — front end, back end, database, deployment — and I've done it for products still serving customers a decade later.
✦ WHAT I DO BEST
My core stack is .NET and C#. As a .NET Developer I build secure, scalable back ends with .NET Core and ASP.NET Core, expose them as clean ASP.NET Web APIs (REST), and back them with Entity Framework and SQL Server, PostgreSQL. As a Full Stack Developer I pair those APIs with responsive front ends in Angular, React, or Blazor, then deploy and scale on Azure with Azure DevOps, Docker, and CI/CD. When a product needs AI, I wire proven models — often through a thin Python layer — into the application without breaking what already works. And when a templated WordPress or Shopify build has hit its ceiling, teams bring me in to rebuild it as a custom .NET web application that can actually grow.
✦ PROOF OF WORK
Longevity is the point. I once took a rough idea from an automotive client and built it into an e-commerce platform that has served customers for nearly 15 years and still runs today. As the lead .NET Developer on Launch Control, a real-estate SaaS, I refactored the core and made the system 50x faster. I also built SiftScore, an AI-powered talent-acquisition platform that uses the OpenAI API to source and score large datasets. Across fintech, real-estate, and healthcare I've owned the full lifecycle as a Full Stack Developer: requirements, architecture, build, go-live.
🚀 SaaS MVP (From Idea → Production)
When a client starts from a rough idea, I take it the full way: requirements, architecture, prototyping, build, and go-live on Azure. As a Full Stack Developer I've shipped .NET SaaS MVPs for fintech, real-estate, and conveyancing platforms — clean, maintainable code with the scalability and monitoring to grow once real customers arrive.
✦ AI Integration for Existing Products
I add AI features when a product actually needs them. The fastest, most cost-efficient path is usually integrating a proven model — OpenAI, Claude, or Gemini, often through a thin Python layer — rather than training your own. I add chatbots, automation, and smart search to existing web apps. Most AI features fail not because of the model but because the surrounding .NET architecture wasn't built to support it — and that's where a senior Full Stack Developer earns their keep.
⚙️ Modernizing Existing .NET Systems - without the rewrite
If you have a .NET or C# application that needs work, I optimize performance, refactor legacy code, upgrade aging ASP.NET back ends, and migrate data access to Entity Framework Core — refactored against SOLID principles, without freezing feature work. Stuck on an old ASP.NET WebForms app? You don't have to gamble on a big-bang rewrite. As a .NET Developer I migrated a WebForms spare-parts store — 20M+ products across 100+ suppliers — to ASP.NET MVC by running both side by side in one solution, so the business kept selling while the modernization happened underneath it. The same incremental approach moves teams off PHP, Laravel, or legacy WordPress builds and onto a maintainable .NET stack: ship value continuously, retire old code gradually, never go dark.
✦ Legacy .NET project modernization
Old code isn't the enemy — downtime is. As a .NET Developer, I modernize legacy ASP.NET and ASP.NET MVC systems by introducing a clean API layer, migrating data access to Entity Framework Core, and refactoring against SOLID principles, all without freezing feature work. As a Full Stack Developer, I migrate the application page by page behind a feature flag, so new and old run together in production and you can switch any screen over — or roll it back instantly — without disrupting users. Whether it's an ASP.NET MVC application that has grown brittle or a WebForms system that needs a path forward, I find the route that lowers risk: incremental, tested, and reversible at every step.
✦ ENTERPRISE-GRADE .NET ARCHITECTURE
My work as a Full Stack Developer goes deeper than features. On a large enterprise fintech platform built on microservices, as a Full Stack Developer I designed how the team builds — onboarding developers, setting architectural standards, and structuring a clean, maintainable .NET codebase that scales. As a .NET Developer with a decade across .NET Framework, .NET Core, ASP.NET, and ASP.NET MVC, plus an M.Sc. in Applied Mathematics behind the design decisions, means I build systems meant to last years, not quarters. I focus on web rather than native mobile apps in Flutter or React Native; on the .NET side I also ship cross-platform with .NET MAUI. I'm a web developer — my C# and .NET expertise powers web applications.
✦ HOW WE'LL WORK
If you need a Full Stack Developer or .NET Developer who can take something from rough idea to production — and keep it running for years — let's talk about the fastest path to shipping it.
.NET Framework
C#
Web Application
React
Node.js
.NET Core
API Integration
Full-Stack Development
ASP.NET MVC
ASP.NET
ASP.NET Core
Angular
WordPress
Microsoft SQL Server
Microsoft Azure
JavaScript
PHP
Python
Software Development
ASP.NET Web API
Andrei M.
Warsaw, Poland
$45/hr
5.0
29 jobs
✅ .NET Full Stack Developer 20+ years of experience
✅ Build powerful .Net solutions that drive business growth
✅ C# .Net developer with 15+ years of experience
✅ Developed 50+ applications
✅ Crafted 200+ user-friendly interfaces that drive real business results.
The clients say
"It doesn't feel like outsourcing, but instead like we have our own remote developers."
"They had great soft and hard skills and were full of ideas and drive!"
I lead the fullstack and mobile development team at Itexus, a professional software development and consulting company focused on Fintech, Insurance, Healthcare, etc.
I have 20+ years of experience in the .net architect development of web and mobile applications, .net, python, node.js, java developer as well as javascript, react .net, angular, AI frameworks and libraries.
👨💻.NET Full Stack Expertise
.NET full stack – strong background in End-to-end development from database to UI using Microsoft stack
.NET Core – deep expertise, cross-platform backend services
.NET Angular – Full stack development on .NET backend and Angular frontend for enterprise-grade solutions
.net core angular – Building complete systems with seamless backend–frontend integration
.NET Core Angular – Scalable and secure web apps using .NET Core and Angular
Angular .NET solutions – Using Angular for UI and .NET for API and business logic
.net core developer – Proven experience delivering high-performance backend solutions using .NET Core
.net core react – Building robust, scalable web applications with .NET Core APIs and React frontends
c# .net developer – End-to-end development expertise using C# and the .NET ecosystem
c# .net core – Advanced solutions built on C# with .NET Core for modern, cross-platform applications
👨💻 BACKEND Development
Python: Expert in Python for server-side development
Frameworks: Proficient in Django and Flask for building web applications
Databases: Skilled in SQL, PostgreSQL, MySQL, and MongoDB for efficient data management
Architecture: Experienced in applying MVC patterns for scalable applications
APIs: Capable of integrating external services through REST and GraphQL
👨💻 FRONT END Development
Proficient in HTML5, CSS responsive, JavaScript
Experienced in React.js, Angular, Vue.js, react native, ionic, xamarin developer
Responsive, cross-browser, ui/ux designer, ux/ui dashboard, ui ux designer app
👨💻AI TOOLS
OpenAI API, DeepFace, ML/DL frameworks (TensorFlow, Keras, PyTorch, Scikit-learn), LangChain, Mistral, AgenticAI, Transformers
RAG + custom AI tools: Document recognition and processing, Market Grabber, project management bots, AI for telephony, video/audio analysis
Mobile App Development
Native Mobile Development: Android, Kotlin, Java, iOS, Swift, KMP, KMM.
Cross-Platform/Hybrid App Development: Flutter, Swift, Objective C, React Native, Xamarin, MAUI.
General Expertise
Website & Full Stack Development: Full stack development with ai .net full stack developer, .net software engineer, .net programmer, full stack developer, ai python full stack developer django, full stack web developer, full stack development, cms developer
DevOps/DevSecOps: AWS, Azure, Docker, Kubernetes, GitLab-CI, Ansible, Terraform, etc
Cross-platform app building with three.js, web application design, webflow web designer, website builders
Integration tools: Data integration, websockets, ABP Framework, discord, Autotask
Experienced in .net core web api, fullstack .net developer roles, with strong skills as a .net specialist. Skilled angular .net react developer, java developer with solid c sharp expertise. Worked on kogito for business automation, delivered ui ux-focused solutions. As an azure data engineer, handled scalable data pipelines. rust developer, python projects include backend developer tasks. Built app as a xamarin and web developer using java and javascript. Skilled in postgresql and web scrapping. Maintained legacy systems with .net webform. Collaborated with nft marketers, managed nft collab manage tasks. Full stack with react nodejs, modern react, including react typescript, react native developer roles. Acted as product owner in agile teams. Cloud deployments done on azure. Built interactive UIs using blazor.
Why Choose us
Microsoft certified talented developers and senior .net developer team
High QA standards, including qa engineer roles
Modern solutions: NFT programmer, metaverse, Microsoft .net, windows 10, Power Apps developer, SharePoint, market grabber
Scalable team: full stack software developer, front end programmer, ios developer, ui ux designer
Industries
Banking, Trading, Cryptocurrency, Asset Management, Lending, Retail, Real Estate & Property Management, Food Delivery, Entertainment, Hospitality, Construction, Sports & Fitness, Travel & Tourism, Wellness, Medical Dashboard, Marketplace, E-commerce, Automotive, Human Resources, Education, E-learning, AI Assistants
Seek new projects to put our .net ai, bring value to individuals, startups, companies.
.NET Framework
C#
React
Angular
JavaScript
ASP.NET Core
Mobile App Development
Android App Development
iOS Development
Artificial Intelligence
TypeScript
Web Application
AI Development
Android
AI Agent Development
Python
Node.js
React Native
MySQL
Django
Aliaksei M.
Gdansk, Poland
$35/hr
5.0
55 jobs
✔ 100% Job Success
✔ 15+ years experience
✔ 4000+ hours worked on Upwork with excellent client feedback.
I'm an experienced software engineer who has spent 11+ years designing and developing various win, web and mobile applications. My main principals are the following:
- Clean code,
- Automation of processes,
- Lack of nothings.
Important to say, that I always try to find simple and elegant solutions for complex technical problems. Satisfied customers and thankful clients are the main factors that can confirm my professionalism
● General
⠀⠀✔ C# ✔ .Net ✔ Design Patterns ✔ MS Visual Studio ✔ DevExpress XAF
● Web Dev
⠀⠀✔ ASP.NET MVC ✔ ASP.NET Web API ✔ WCF ✔ JavaScript ✔ jQuery
● ORM
⠀⠀✔ Entity Framework (Code-First, Database First) ✔ XPO
● Database
⠀⠀✔ T-SQL ✔ MS SQL ✔ MySQL ✔ MongoDB ✔ Oracle ✔ PostgreSQL
● Version Control System
⠀⠀✔ TFS ✔ Git
● Reports
⠀⠀✔ Crystal Reports ✔ Fast Report ✔ DevExpress Reports
● CMS
⠀⠀✔ Umbraco
● Other skills
⠀⠀✔ Data Scraping ✔ Parsing
Feel free to contact to know more about my work and how I can help you.
.NET Framework
C#
ASP.NET
SQL
ASP.NET MVC
JavaScript
DevExpress
Microsoft Azure
Eugene K.
Warsaw, Poland
$33/hr
5.0
4 jobs
.NET Developer with over 15 years of experience. I help companies build scalable .NET backend and frontend. Worked on projects for Microsoft and Shell. 97% of my clients are satisfied with my work.🧑💻Interested in building scalable enterprise and startup systems. Let's create powerful software together!
Are you in search of a Senior .NET Developer who can build, scale, and maintain resilient software systems for web, desktop, and cloud-based applications? You’re in the right place. I’m Eugene - a seasoned .NET developer with deep expertise in full-stack architecture, Azure-based services, REST APIs, relational databases, and scalable backend platforms.
Over the years, I’ve taken the lead on mission-critical software projects for top-tier clients, including Microsoft and Shell. I’ve delivered a wide array of business solutions using C#, ASP.NET Core, .NET Stack, Entity Framework, SQL Server, PostgreSQL, WPF, WinForms, and Azure App Services. My portfolio includes scalable web platforms, API-driven microservices, high-performance desktop tools, and cloud-native architectures powered by Docker and CI/CD workflows.
👨💻 Areas Where I Excel:
✅ Full-Stack .NET Development
I craft backend and frontend solutions with ASP.NET Core, .NET 6/8, MVC, Razor Pages, and Web API. I also bring experience with Blazor, Angular, and React, following clean architecture and SOLID design.
✅ Desktop Application Engineering
I build Windows apps using WPF, WinForms, MVVM, and Telerik controls. These include hardware integrations, PDF/image processing, and offline functionality.
✅ API Development & Integration
I create and connect REST APIs with third-party services such as Stripe, Twilio, SendGrid, and CRM systems. I also develop custom APIs for tools like print services and internal dashboards.
✅ Database Architecture & Optimization
I design performant database schemas and manage SQL Server, PostgreSQL, MySQL, and Cosmos DB. I focus on query performance, indexing, and schema evolution.
✅ Cloud & DevOps
I deploy apps using Azure App Services, Functions, and CI/CD with GitHub Actions or Azure DevOps. I containerize services with Docker and orchestrate deployments via Kubernetes.
✅ Microservices & Distributed Architecture
I build .NET Core microservices with RabbitMQ, Kafka, and Ocelot. These systems serve web and mobile platforms with real-time and asynchronous communication.
🔍 Key Project Highlights:
iGaming Platform: Built a real-time casino system using .NET Core, SignalR, Kafka, ScyllaDB, ClickHouse, PostgreSQL, ELK stack, and Power BI. Deployed via Docker on AWS.
Loan Automation: Delivered a full-cycle loan platform with .NET Core, OData, EF Core, Azure Service Bus, Hangfire, CosmosDB, Angular, and Power BI.
App Marketplace: Developed a microservice-based SaaS platform with RabbitMQ, Stripe, Angular 6, Ocelot, Autofac, and SQL Server.
Fleet ERP: Built WPF/Angular tracking ERP with EF6, SQL Server, MEF, GIS, and modules for driver behavior, fuel tracking, and maintenance.
Insurance System: Created a UBI platform on ASP.NET Core, AngularJS, Kendo UI, and MS SQL for fraud detection and claims processing.
Outlook CRM: Developed CRM integration for Outlook using ASP.NET MVC, AngularJS, Kendo UI, Azure Services, and hosted on IIS.
Logistics ERP: Led development of a WPF .NET AngularJS ERP for transport tracking, satellite communication, and business ops.
Medical Monitoring: Built a diagnostics app with ASP.NET MVC, DurandalJS, EF, and MS SQL. Hosted securely via IIS.
Delivered enterprise-grade .NET solutions: real-time, cloud, ERP, CRM, fintech, and diagnostics systems.
🛠️ My Technical Toolbox:
I specialize in C# and the .NET ecosystem, including .NET Core, .NET Framework, Web API, MVC, and WinForms. I rely on EF and LINQ for data access and schema control. My database experience covers MS SQL, PostgreSQL, MySQL, MongoDB, Redis, and Cosmos DB. I manage deployments on AWS and Azure, using Azure DevOps, Docker, and Git. For UIs, I use WPF, Blazor, Angular, and React with TypeScript. I also implement secure CI/CD, API integrations, and scalable infrastructure.
Why Teams Work with Me:
✔️ I have over 15 years of professional engineering experience (more than 5 years of experience)
✔️ I possess expertise in both cloud and desktop software solutions
✔️ I have a proven ability to deliver enterprise-level applications
✔️ I possess an in-depth knowledge of DevOps and backend performance tuning
✔️ I can provide AI chatbot (AI Agents) development and workflow automation.
✔️ I have a high ownership, transparency, and quality focus
✔️ My English is fluent, and I can work both with international teams and independently.
I collaborate with clients who value architecture, efficiency, and clean code. Whether your project is just starting or mid-scale, I bring clarity, experience, and technical strength to push it forward.
Let’s connect and bring your vision to life with robust .NET development.
.NET Framework
C#
Entity Framework
React
Angular
Microsoft SQL Server
Kubernetes
CI/CD
DevOps Engineering
ASP.NET MVC
ASP.NET Web API
Web API
API Integration
.NET Core
ASP.NET
Burak Kaan K.
Wroclaw, Poland
$35/hr
5.0
13 jobs
I help businesses build reliable, scalable applications across mobile, desktop, and cloud using modern .NET technologies.
With 15+ years of experience, I’ve delivered production systems used by thousands of users — from cross-platform apps to complex backend services. I focus on clean architecture, performance, and long-term maintainability, and I actively leverage AI tools to accelerate development and improve product quality.
What I can help you with
• Cross-platform apps (iOS, Android, Windows, macOS) using .NET MAUI / Xamarin
• Windows desktop applications (WinUI 3, UWP, WPF)
• Backend systems and APIs (ASP.NET Core, REST, SignalR, authentication)
• Azure cloud solutions (App Services, Functions, Azure SQL, Storage, CI/CD)
• System design and microservices architecture
• Integrating third-party APIs and services
• Modernizing legacy projects (Xamarin → MAUI, UWP → WinUI, .NET Framework → .NET 8/9)
AI-Enhanced Development
Experienced in AI-assisted development workflows (“agentic coding”) to deliver faster without sacrificing quality. Skilled in using modern AI tools to improve productivity, code quality, and problem-solving. Hold certifications related to AI and modern development practices
Why clients work with me?
• I design systems that are scalable and maintainable long-term.
• I write clean, well-structured, production-ready code.
• I communicate clearly and deliver reliably.
• I can take full ownership or integrate seamlessly with your team.
If you’re looking for a senior engineer who combines strong fundamentals with modern AI-driven efficiency, I can help you move your project forward quickly and safely.
Let’s discuss your project.
C#
SQLite
Universal Windows Platform
Microsoft Azure
Location-Based Service
Windows Phone
iOS Development
Microsoft Bot Framework
Azure App Service
XAML
Xamarin
Anton M.
Warsaw, Poland
$20/hr
5.0
35 jobs
I’m a Senior .NET Developer with over 15 years of hands-on experience building robust, high-performance desktop applications using technologies like WPF (MVVM), WinUI 3, and Windows Forms. I specialize in delivering smooth, modern user interfaces and stable architecture for Windows-based solutions.
Tech Stack & Skills:
▪️ UI/UX: WPF (MVVM), WinUI 3, Windows Forms, GDI+
▪️ .NET Ecosystem: .NET (C#), ADO.NET, Entity Framework, LINQ, WCF, ASP.NET MVC
▪️ Databases: MS SQL Server, SQLite, LightDB
▪️ APIs & System Integration: WinAPI, Azure integration, Google Cloud Platform
▪️ Other Languages: Solid experience in Python and working with LLMs
Education:
▪️ MSc in Artificial Intelligence
.NET Framework
C#
Windows Presentation Foundation
Windows Forms
Desktop Application
Microsoft Windows
Standalone Application
Reverse Engineering
.NET Core
Windows App Development
Model View ViewModel
XAML
Artificial Intelligence
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