I will fix bugs and add features in asp net core web API, mvc and sql server


About this gig
Is your ASP.NET Core app throwing 500 errors, failing to build after an update, or stuck on a slow SQL Server query? Or do you need a new feature added without breaking what already works? That's the work I do.
I'm a C# developer with several years of experience on a large production ASP.NET and SQL Server system, so working inside someone else's code is normal for me.
What I can help with:
- Web API and MVC bugs, exceptions, and build errors
- New endpoints, pages, or a full module
- EF Core queries, migrations, and stored procedures
- Slow queries, checked against the real execution plan
- Login with ASP.NET Core Identity or JWT, with roles
- Swagger docs, xUnit tests and SignalR features
- Moving an old .NET Framework app to .NET 8 or 10
How I work:
I reproduce the problem first and fix the cause, not just the symptom. Every delivery comes with a short report: what broke, why, what I changed, and how you can check it. Each bug fix ships with a test, so the same bug doesn't come back next month.
Not sure which package fits? Send me the error or a few lines about the task before ordering. I'll tell you honestly what it needs.
Get to know Emon
Software Engineer
- FromBangladesh
- Member sinceJan 2025
- Avg. response time1 hour
Languages
Bengali, English
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FAQ
Which .NET versions do you work with?
.NET 6 up to .NET 10, plus older .NET Framework 4.x apps (MVC 5 and Web API 2). If your project is on something older, send me the details first, and I'll check before you order.
What do you need from me to get started?
Access to the code (a GitHub, GitLab, or Azure DevOps invite, or a ZIP), the exact error or the steps to reproduce it, and a database backup or script with test data. Please remove real customer data before sharing.
What if my bug turns out bigger than the package?
I look at the code before I start. If it needs more work than the package covers, I'll tell you right away and send a custom offer for the extra part. You won't get a half-fix dressed up as a finished one.
Will you work on my live server or production database?
I work on a local copy or a staging server and hand over the changes for you to deploy. If the bug only shows up in production, the logs and read-only access are usually enough to find it.
Do I get the full source code?
Yes. I can push the changes to your repository as a branch or pull request, or send them as a ZIP file. The code I write for your project is yours once the order is complete.
My project has no tests at all. Can you still add them?
Yes. If there's no test project yet, I set one up with xUnit and add tests around the code I change. If you want tests for older parts of the app too, I can add them as an extra.
Can you make a slow page or API faster?
Most of the time, yes. I check the actual execution plan, missing indexes, N+1 queries, and heavy EF Core includes. You get before-and-after timings, so you can see the difference yourself.
How do you use AI tools?
I write code myself and also use AI coding assistants such as Claude Code. Every change is reviewed line by line and tested before delivery, and I take full responsibility for it. Your code goes to an AI tool only if you agree. Want no AI at all? Just tell me before ordering.

