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You will get critical bugs fixed in your existing .NET application

Ajithkumar K.Status: Offline
Ajithkumar K. Ajithkumar K.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Ajithkumar, priced and ready to go.
Ajithkumar K.Status: Offline
Ajithkumar K. Ajithkumar K.
5.0
Top Rated
Preview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Ajithkumar, priced and ready to go.

Project details

You will get critical bugs fixed in your existing .NET application with a focus on stability, clean resolution, and long term maintainability. I troubleshoot and resolve issues in ASP.NET, .NET Core, WinForms, Web API, and enterprise applications, including crashes, broken functionality, performance bottlenecks, and production errors.

This service is ideal for urgent bug fixing, hidden event issues, unexpected exceptions, deployment problems, and difficult defects that require senior level debugging.

My approach includes root cause analysis, safe fixes, code validation, and delivery of clean updated source code so your application runs reliably without introducing new issues.
Programming Languages
JavaScript, ASP.NET, C#
Coding Expertise
Cross Browser & Device Compatibility, Performance Optimization, Security
What's included
Service Tiers Starter
$200
Standard
$390
Advanced
$670
Delivery Time 2 days 4 days 7 days
Number of Revisions
123
Bug Investigation
Fix Documentation
-
Detailed Code Comments
-
-
5.0
24 reviews
100% Complete
(24)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

JO

John O.
5.00
May 26, 2026
Visual Studio C# .NET SQL Issue Resolution Ajith was great to work with and incredibly knowledgeable. I’d highly recommend him if you run into any roadblocks like we did.

He helped us get a new ASP.NET C# project running in Visual Studio 2026 after moving from our older 2012 setup. We ran into several version‑related issues—scope errors, SQL connectivity, a small code bug, IE configuration, and publishing—but he walked us through all of it.

We wouldn’t have met our deadline without his expertise.

EW

Eagle W.
5.00
May 4, 2026
Web API Integration Specialist Needed

OH

Olivia H.
5.00
Mar 30, 2026
.NET Developer Thank you for a fast and good result!

AR

Aswin R.
5.00
Feb 23, 2026
Scrap websites and turn them into the required JSON Format

NT

Nathan T.
5.00
Feb 11, 2026
Help with Azure web app and github source deployment Ajithkumar did exactly what I needed him to do in a timely manner.
Ajithkumar K.Status: Offline

About Ajithkumar

Ajithkumar K.Status: Offline
.NET Developer .NET Architect .NET Expert ASP.NET Core MVC, C#, CTO
95% Job Success
5.0  (24 reviews)
Thoothukudi, India - 1:50 pm local time
Full Stack Senior .NET Developer and .NET Architect specializing in SaaS application development, enterprise software architecture, backend engineering, and scalable cloud solutions. With years of practical experience, I build secure, high-performance web platforms using .NET, ASP.NET Core, Azure, SQL Server, and JavaScript frameworks, helping businesses launch reliable digital products faster.

⚙️ Backend Expertise

🌳 .NET Framework, ASP.NET Core, C#
🌳 Scalable REST API Development, Backend Integration
🌳 Microservices, Distributed Systems
🌳 Secure Authentication & Authorization using JWT, OAuth
🌳 Role-Based Access Control, Identity Management
🌳 Clean Architecture

🖼️ Frontend Expertise

🔸 .NET MAUI, Avalonia UI, Blazor, Razor Pages
🔸 Vanilla JavaScript Expert
🔸 ReactJS, NextJS, AngularJS
🔸 Responsive Web Design
🔸 HTML5, CSS3, Bootstrap, Tailwind CSS
🔸 AJAX & REST API Integration
🔸 UI/UX Implementation

🛢 Database Expertise

🌿 Database Architecture
🌿 SQL Server Performance Tuning
🌿 MSSQL, MySQL, PostgreSQL
🌿 Azure SQL, MongoDB, ElasticSearch
🌿 Query Optimization and Data Modeling

🌐 Domain Expertise

🔸 Healthcare Application Development
🔸 SEO Platforms and Marketing Tools
🔸 Cybersecurity Software Solutions
🔸 E-Commerce Platforms
🔸 SaaS Products

☁️ Cloud Expertise

🌱 Microsoft Azure, AWS, Google Cloud Infrastructure
🌱 Nginx Configuration
🌱 Docker, DevOps, CI/CD Pipelines, and Release Automation
🌱 Microsoft Azure Services
🌱 Application Performance Optimization
🌱 Monitoring, Logging, and Reliability Engineering

💼 Services I Provide

🔸 Custom SaaS Product Development from MVP to Production Release
🔸 Enterprise Web Application Development with Secure and Scalable Architecture
🔸 REST API Development, Third-Party Integrations, and Backend Modernization
🔸 Modern Frontend Interfaces with Clean UX and Responsive Design
🔸 Cloud Hosting, Infrastructure Optimization, and Deployment Automation
🔸 Ongoing Product Maintenance, Feature Expansion, and Technical Support

🌟 Recent Integrations

🌲 Amazon SP API / MWS Migration
🌲 Burp Suite Automation / ZAP Integration
🌲 Stripe / PayPal / Razorpay / SlimCD
🌲 OpenAI / Claude / Gemini APIs

Keywords

Senior .NET Developer Upwork
Fractional CTO Upwork
Full-Stack .NET Developer Upwork
ASP.NET Core Developer Upwork
ASP.NET MVC Developer Upwork
C# Developer Upwork
.NET Core Developer Upwork
.NET Backend Developer Upwork
.NET API Developer Upwork
REST API Developer Upwork
Microservices Developer Upwork
Enterprise Application Developer Upwork
SaaS Application Developer Upwork
Cloud Application Developer Upwork
Azure .NET Developer Upwork
SQL Server Developer Upwork
Database Architecture Specialist Upwork
Performance Optimization Specialist Upwork
Software Maintenance & Support Upwork
Application Migration & Upgrade Services Upwork
Third-Party Integration Specialist Upwork

Core Skills

ASP.NET Core, .NET Framework, C#, .NET Core, MVC, Web API, Entity Framework Core, SQL Server, Azure SQL, Microservices, RESTful APIs, SignalR, Blazor, Azure, AWS, Docker, CI/CD Pipelines, Agile Development, Responsive Web Design, Frontend Development, Backend Development, Database Management, Scalable Architecture, Cloud Deployment.

Steps for completing your project

After purchasing the project, send requirements so Ajithkumar can start the project.

Delivery time starts when Ajithkumar receives requirements from you.

Ajithkumar works on your project following the steps below.

Revisions may occur after the delivery date.

Issue Investigation

Analyze the reported bug, review logs, reproduce the issue, and identify root cause.

Bug Fix Implementation

Apply targeted code fixes, validate behavior, and ensure no side effects.

Review the work, release payment, and leave feedback to Ajithkumar.