You will get a high-performance Windows desktop application in .NET & C#
Top Rated
Top Rated
Project details
Need a fast, reliable Windows desktop application built by a senior .NET developer? This is a space very few freelancers do well — and I've built production Windows software for 17 years.
I'm a Senior .NET Developer and Solution Architect — Top Rated Plus, 100% Job Success, $400K+ earned on Upwork. I build robust desktop apps that handle real business workloads.
WHAT I BUILD:
✅ Windows desktop apps in WPF, WinForms, and .NET (C#)
✅ Cross-platform desktop with .NET MAUI (Windows + macOS)
✅ Database-driven apps (SQL Server, PostgreSQL) with clean architecture
✅ Hardware & device integration (scanners/TWAIN/WIA, printers, serial devices)
✅ API, cloud, and third-party service integration
✅ Modernizing legacy desktop apps (old WinForms/VB → modern .NET)
✅ Installers, auto-update, logging, and proper error handling
Built on Clean Architecture and SOLID principles — maintainable software your team can rely on and build on, not a throwaway prototype.
Perfect for: business tools, POS and inventory systems, data-entry and reporting apps, document/scanning software, and desktop tools that talk to your APIs or databases.
Message me with what you need
I'm a Senior .NET Developer and Solution Architect — Top Rated Plus, 100% Job Success, $400K+ earned on Upwork. I build robust desktop apps that handle real business workloads.
WHAT I BUILD:
✅ Windows desktop apps in WPF, WinForms, and .NET (C#)
✅ Cross-platform desktop with .NET MAUI (Windows + macOS)
✅ Database-driven apps (SQL Server, PostgreSQL) with clean architecture
✅ Hardware & device integration (scanners/TWAIN/WIA, printers, serial devices)
✅ API, cloud, and third-party service integration
✅ Modernizing legacy desktop apps (old WinForms/VB → modern .NET)
✅ Installers, auto-update, logging, and proper error handling
Built on Clean Architecture and SOLID principles — maintainable software your team can rely on and build on, not a throwaway prototype.
Perfect for: business tools, POS and inventory systems, data-entry and reporting apps, document/scanning software, and desktop tools that talk to your APIs or databases.
Message me with what you need
Programming Languages
C#, VBOperating System
WindowsDesktop App Expertise
Application Setup & Installation, Development, Software Debugging, Application Review & OptimizationWhat's included
| Service Tiers |
Starter
$299
|
Standard
$699
|
Advanced
$1,199
|
|---|---|---|---|
| Delivery Time | 7 days | 14 days | 21 days |
Number of Revisions | 1 | 2 | 3 |
Bug Investigation | |||
Source Code | |||
Database Integration | |||
Detailed Code Comments | |||
Fix Documentation |
Frequently asked questions
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MS
Mel S.
May 3, 2026
30 minute consultation
Tarang understood our ask and answered all of our questions clearly during our consultation.
KW
Kanchan W.
Aug 12, 2025
Full Stack Developer Needed: Next.js & C# Expertise Required
Great full stack developer—highly responsive and a clear, proactive communicator who keeps stakeholders aligned. Demonstrates sharp attention to detail and deep code understanding, moving confidently across frontend and backend. Reviews are reliable and constructive; they catch edge cases, improve readability, and raise overall code quality. Pragmatic under pressure, they unblock teammates quickly and balance speed with maintainability. Consistent impact on delivery and team effectiveness.
KH
Kelvin H.
Jul 18, 2025
Application integration as per discussion with Alistair Farquharson.
SG
Shlomi G.
Jul 15, 2025
Mobile Dating Application Development
HF
Hiba F.
Apr 22, 2025
30 minute consultation
About Tarangkumar
Full Stack .NET Developer | AI Integration, Chatbot & Agent Architect
100%
Job Success
Surat, India - 12:21 pm local time
Anyone can call an AI API. Very few can architect a system where that AI is secure, scalable, and reliable inside a real enterprise application. That's the gap I fill. With 17 years building and scaling .NET applications and a 100% Job Success score across 240+ Upwork jobs, 26,000+ hours, and $400K+ earned I own the outcome, not the ticket.
🏗️ .NET ARCHITECTURE (MY FOUNDATION)
Architecture is what separates software that scales from software that collapses under load. I design and build on the latest Microsoft stack: .NET 10 / .NET 9, C# 13, ASP.NET Core, Minimal APIs, and Web API.
I structure systems with Clean Architecture, Domain-Driven Design (DDD), CQRS, and Vertical Slice Architecture, and build cloud-native, distributed systems using microservices, .NET Aspire, gRPC, and message-based communication. Data layer in Entity Framework Core with PostgreSQL and SQL Server, caching with Redis, containerized with Docker and Kubernetes, deployed on Azure and AWS with full CI/CD. Multi-tenancy, soft-delete, security, and cost are designed in from day one not patched in later.
💻 FULL STACK DEVELOPMENT (END TO END)
I own the entire build, no handoffs. Front end in React 19 and Next.js 15 (App Router, Server Components, SSR/ISR), with TypeScript, Tailwind CSS, and modern component architecture. Back end in C#, ASP.NET Core, and Node.js / Express for lightweight services and real-time features. REST and GraphQL APIs, WebSockets/SignalR, authentication (JWT, OAuth, Identity), Stripe payments, and third-party integrations. One senior developer taking your product from database schema to deployed UI.
🧠 AI INTEGRATION (MY CORE SPECIALTY)
This is where the market is moving, and it's exactly what my architecture background makes me credible for. I embed LLMs into your existing software the right way: RAG (retrieval-augmented generation) so your AI answers from YOUR own documents and data, vector search with pgvector / Azure AI Search, AI agents that take real actions, MCP (Model Context Protocol) tool servers, and multi-agent workflows. Built on the enterprise Microsoft AI stack Azure OpenAI, OpenAI API, Microsoft.Extensions.AI, Semantic Kernel, and Microsoft Agent Framework (MAF 1.0) plus function calling, embeddings, and prompt engineering. Enterprise-grade: secure, observable, and production-ready.
🤖 AI CHATBOTS & ASSISTANTS
Custom AI chatbots and assistants for your website, product, or internal tools powered by GPT / Azure OpenAI and connected to your real business data so answers are accurate, not generic. Lead capture, 24/7 support, and internal knowledge assistants that actually know your company.
WHY CLIENTS KEEP HIRING ME:
✔ 17 years of real .NET depth not a bootcamp, not a thin wrapper around ChatGPT
✔ True architect-level thinking: security, multi-tenancy, scalability, and cost built in
✔ Full stack ownership one person, whole system, predictable delivery
✔ Clear communication and clean, maintainable code you can build on after I'm gone
✔ Certified: Microsoft Certified Professional, PMI Generative AI, Google Project Management
TECH STACK:
C#, .NET 10, .NET 9, ASP.NET Core, Minimal APIs, Web API, Microservices, Clean Architecture, DDD, CQRS, .NET Aspire, Entity Framework Core, gRPC, React 19, Next.js 15, Node.js, Express, TypeScript, Tailwind CSS, PostgreSQL, SQL Server, Supabase, Redis, Azure, AWS, Docker, Kubernetes, CI/CD, Azure OpenAI, OpenAI API, RAG, AI Agents, Microsoft Agent Framework, Semantic Kernel, MCP, pgvector, Generative AI, LLM, Stripe.
TYPICAL PROJECTS:
- Add an AI chatbot or assistant to an existing product
- "Chat with our documents/data" (RAG) systems
- AI agents that automate a real business workflow
- Integrate AI into a legacy .NET application
- Architect and build a full SaaS platform (.NET + React/Next.js)
- Build multi-tenant SaaS with subscription billing (Stripe)
- Design database schema and API architecture from scratch
- Rescue, refactor, or modernize an existing .NET codebase
INDUSTRIES I'VE DELIVERED FOR:
SaaS, FinTech, Healthcare, Hospitality, E-commerce, Logistics, and Real Estate / PropTech building secure, compliant, multi-tenant systems for each.
If you have an app and want AI in it or want the whole thing architected and built by one senior developer who won't disappear message me with what you're trying to do. I'll tell you honestly whether I'm the right fit and how I'd approach it.
Steps for completing your project
After purchasing the project, send requirements so Tarangkumar can start the project.
Delivery time starts when Tarangkumar receives requirements from you.
Tarangkumar works on your project following the steps below.
Revisions may occur after the delivery date.
Initial Consultation
We'll discuss your project requirements, goals, and timeline to ensure we are aligned.
Requirement Gathering
I will gather detailed specifications, including features, design preferences, and any specific technologies you want to use.