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I will fix bugs, optimize ef core, upgrade your aspnet application
Francisco S.
About this gig
Is your .NET application crashing, running slow, or stuck on an old framework version?
Bad database queries and legacy code can ruin your business. I am a Senior C# Developer specializing in troubleshooting, debugging, and modernizing .NET architectures. I will act as your "Backend Sniper" to identify the root cause and fix it surgically without breaking existing features.
My Expertise Includes:
- Fixing API errors, crashes, and unhandled exceptions.
- Optimizing Entity Framework Core (solving N+1 query issues, slow loads).
- Upgrading legacy projects (.NET 5/6/8) to the latest .NET 10.
- ️Resolving complex SQL Server Database migration errors and Foreign Key crashes.
Stop losing customers over slow load times or broken features.
Send me a message with your bug details and I will evaluate it immediately!
Get to know Francisco S.
Francisco S.
Full Stack NET Developer And Stripe Integration Expert
- FromPortugal
- Member sinceSep 2023
- Avg. response time1 hour
Languages
English, Portuguese, Spanish
Hi, I'm Francisco, a Senior Backend Developer & .NET Architect.
Stop wasting time with slow architectures. I build, fix, and scale robust backend systems in .NET (C#) to ensure your app runs flawlessly.
Core Expertise:
• Architecture: ASP.NET Core (.NET 10), REST APIs, SignalR
• Databases: SQL Server & EF Core optimization
• SaaS & Integrations: Stripe Webhooks, Twilio, external APIs
• Code Rescue: Advanced debugging & legacy upgrades
I solve business problems with secure and scalable code. Ready to build something reliable? Send a message to discuss your project!
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FAQ
What if the bug is too complex or outside your scope?
Please always message me before ordering! If I review your code and realize it requires a massive architectural rewrite instead of a simple fix, I will let you know honestly before you spend any money.
How do I share my code with you securely?
You can invite me to your GitHub, Bitbucket, Azure DevOps repository, or simply send a zipped folder of the source code (without the bin/obj folders).
Will upgrading to .NET 10 break my current application?
I perform all upgrades in a separate Git branch. I fix the breaking changes caused by deprecated packages and ensure the project compiles and runs perfectly before delivering the updated code back to you.
