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You will get ASP.NET Core API & MVC Bug Fixing, Optimization and Support

Alpesh M.Status: Offline
Alpesh M. Alpesh M.
4.9
Preview imagePreview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Alpesh, priced and ready to go.
Alpesh M.Status: Offline
Alpesh M. Alpesh M.
4.9
Preview imagePreview image

Let a pro handle the details

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

Project details

Are you struggling with bugs, performance issues, API errors, database problems, or authentication failures in your ASP.NET Core application?

I will help you diagnose, fix, and optimize your ASP.NET Core Web API or MVC application quickly and efficiently.

With 8+ years of experience in ASP.NET Core, C#, SQL Server, Entity Framework Core, and enterprise application development, I can resolve backend issues, API integration problems, database bottlenecks, authentication errors, and performance-related challenges.

Services include:

✔ ASP.NET Core Web API bug fixing

✔ ASP.NET MVC troubleshooting

✔ SQL Server query optimization

✔ Entity Framework Core fixes

✔ Authentication & Authorization issues

✔ API integration troubleshooting

✔ Performance optimization

✔ Code review and refactoring

✔ Deployment and configuration support

I focus on delivering clean, reliable, and maintainable solutions that improve application stability, performance, and user experience.

Contact me before placing an order so we can discuss your requirements and choose the right package
Programming Languages
JavaScript, ASP.NET, C#
Coding Expertise
PSD to HTML, Security, W3C Markup Validation Service
What's included
Service Tiers Starter
$30
Standard
$75
Advanced
$150
Delivery Time 3 days 7 days 10 days
Number of Revisions
123
Bug Investigation
Fix Documentation
Detailed Code Comments
-

Frequently asked questions

4.9
24 reviews
92% Complete
(22)
8% Complete
(2)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

PP

Panagiotis P.
5.00
Jan 25, 2026
C# Code documentation and comments to working branch

PP

Panagiotis P.
5.00
Dec 11, 2025
Customer Registration Service good developer

AR

Andy R.
5.00
Dec 11, 2023
fix broken mysl_connect file due to PHP upgrade

EA

Eszter A.
5.00
Dec 21, 2022
Developer needed to create simple report based on API

SP

Steven P.
5.00
Jan 16, 2022
Simple Login and user management Responsive and over delivered early
Alpesh M.Status: Offline

About Alpesh

Alpesh M.Status: Offline
ASP.NET Developer | ASP.NET Core | ASP.NET Web Developer | ASP.NET MVC
100% Job Success
4.9  (24 reviews)
Ahmedabad, India - 6:07 am local time
Senior ASP.NET Developer / .NET Full-Stack Developer with 15+ years of experience building, modernizing, maintaining, and integrating web applications, SaaS platforms, eCommerce systems, and business applications.

I specialize in ASP.NET Core, .NET, C#, ASP.NET MVC, Web API, Angular, React, TypeScript, JavaScript, SQL Server, Entity Framework, REST APIs, and third-party API integrations.

Core Expertise:

✔ ASP.NET / .NET Development: ASP.NET Core / .NET 7 / .NET 8, C#, Web API, Entity Framework, SQL Server, Legacy Modernization.
✔ Frontend: Angular, React, TypeScript, Responsive SPA applications.
✔ API & System Integration: REST/SOAP APIs, Payment Gateways, ERP Integration, Webhooks.
✔ eCommerce & Marketplace: Amazon SP-API / MWS, eBay API, Walmart API, Inventory & Order Synchronization.
✔ Database & Performance: SQL Server Optimization, Query Tuning, Caching.

Cloud & Deployment

✔ Azure App Service / Azure SQL / Service Bus / API Management
✔ AWS EC2 / S3 / RDS
✔ IIS / Windows / Linux deployment

AI & Automation

✔ OpenAI / ChatGPT API integration
✔ AI agents & business automation
✔ n8n / MCP integrations

I Can Help With

• Amazon SP-API & eBay Integration
• Legacy ASP.NET Modernization
• .NET Web API & REST API Development
• Full-Stack Application Development (Angular/React + .NET)
• Database Optimization & Performance Tuning

With 15+ years of development experience and a strong background in complex business and eCommerce systems, I focus on reliable, scalable, and maintainable solutions.

If you need a Senior ASP.NET Developer, .NET, C#, Angular, React, or Full-Stack Developer, I can help build, fix, modernize, integrate, and maintain your application.

⭐ Full-Stack ASP.NET Developer Expertise

I work across the complete application stack, from database and backend architecture to modern frontend development. I can take an existing application, understand the architecture, fix issues, develop new features, build APIs, connect frontend applications, optimize the database, and deploy the solution to production.

Backend: ASP.NET Core, ASP.NET MVC, C#, .NET, Web API, REST API, Entity Framework Core, LINQ, Dapper, ADO.NET

Frontend: Angular, React, TypeScript, JavaScript, HTML, CSS, Bootstrap, jQuery, AJAX

Database: Microsoft SQL Server, MySQL, MariaDB, stored procedures, database design, query optimization and performance tuning

I've worked as an ASP.NET Web Developer on the full stack for 15+ years with Angular, React, jQuery, TypeScript, JavaScript, HTML5 and CSS: 4 SPAs delivered, 300+ UI components, Lighthouse above 90. I'm a full stack developer who owns both the C# backend and the UI.

I've been a backend developer on C# .NET (C sharp) 15+ years: ASP.NET Core, ASP.NET MVC, ASP.NET Web API, .NET Framework, .NET Core and Entity Framework, 350+ REST API endpoints shipped, 35+ third-party API integrations (payment, carrier, CRM), SignalR real-time features for 65000+ concurrent users, and databases up to 800 GB and 80M rows on SQL Server, Postg


💡 Why Clients Hire Me: I focus on reliable, scalable, and maintainable solutions. Whether you need a complete application, a secure Web API, database optimization, or ongoing support, I work across the entire technology stack to deliver results.

If you are looking for an experienced ASP.NET Developer, ASP.NET Core Developer, .NET Developer, C# Developer, Web API Developer, Angular Developer, React Developer, or Full-Stack .NET Developer, I can help you design, develop, integrate, optimize, and maintain reliable web applications and API-driven systems. I have extensive experience with ASP.NET Core, ASP.NET MVC, C#, .NET Web API, REST API, SQL Server, Entity Framework, Angular, React, PHP, Laravel, and custom software development, including complex eCommerce and marketplace integrations.

My API and eCommerce integration experience includes Amazon SP-API, Amazon Vendor API, Amazon Business API, Amazon Ads API, Amazon PPC, Amazon Advertising API, Amazon MWS, Walmart API, Etsy API, eBay API, Amazon Marketing Stream, Amazon Marketing Cloud, and third-party API integration. I have worked on Amazon Seller Central automation, Amazon Seller Automation, Amazon FBA, Amazon FBM, inventory management, order management systems, eCommerce applications, marketplace integrations, and business process automation, helping businesses connect multiple platforms and automate their operations.

I also work with modern AI and automation technologies, including Claude API, MCP Server, AI Agents, and custom AI integrations, along with application performance and speed optimization. Whether you need an ASP.NET Core application, ASP.NET MVC modernization, C# backend, REST API, Full-Stack Developer, eCommerce integration, marketplace API integration, or custom software development, I can provide end-to-end web development and ongoing technical support.

Looking for expert Asp.net Web Developer? Want to grow your business with Advance Web Application or Website Development?

Steps for completing your project

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

Delivery time starts when Alpesh receives requirements from you.

Alpesh works on your project following the steps below.

Revisions may occur after the delivery date.

Issue Analysis & Requirements Review

Review the reported issue, error logs, screenshots, source code, and environment details to identify the root cause.

Bug Investigation & Resolution

Investigate the issue, apply fixes, test the solution, and ensure the problem is resolved without affecting existing functionality.

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