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You will get Professional ASP.NET Core bug fixing

Rostyslav L.Status: Offline
Rostyslav L.
Preview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Rostyslav, priced and ready to go.
Rostyslav L.Status: Offline
Rostyslav L.
Preview image

Let a pro handle the details

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

Project details

I will investigate and fix ASP.NET Core backend issues, API errors, database problems, integration failures, and performance bottlenecks.

I work with C#, ASP.NET Core, REST APIs, PostgreSQL, RabbitMQ, Docker, and production systems. I focus on finding the root cause quickly and delivering a clean, maintainable fix rather than a temporary workaround.

This service is ideal for existing .NET applications that have bugs, failing API calls, SQL issues, integration problems, timeouts, or unexpected production behavior.
Programming Languages
ASP.NET, C#
Coding Expertise
Performance Optimization, Security
What's included
Service Tiers Starter
$99
Standard
$199
Advanced
$399
Delivery Time 2 days 4 days 7 days
Number of Revisions
235
Bug Investigation
Fix Documentation
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Detailed Code Comments
-

Frequently asked questions

Rostyslav L.Status: Offline

About Rostyslav

Rostyslav L.Status: Offline
Full-Stack .NET Developer | APIs | Blazor | PostgreSQL
Wuppertal, Germany - 10:32 am local time
Full-Stack .NET Developer with 5+ years of professional software development experience, building and supporting production systems in enterprise environments.

My main stack is C# / .NET, ASP.NET Core, Blazor, PostgreSQL, RabbitMQ and Docker. I work across backend, frontend and integrations — from REST APIs and database logic to UI features, messaging and production troubleshooting.

I can help with:

- ASP.NET Core APIs and backend development
- Blazor web applications
- PostgreSQL / SQL development and debugging
- RabbitMQ and system integrations
- Dockerized applications
- Bug fixing and production issues
- Existing .NET application maintenance and feature development
- Legacy Java / Oracle systems when needed

I have hands-on experience with warehouse and logistics software, business-critical integrations and production environments where reliability and maintainability matter.

I’m especially effective on clearly scoped tasks where you need someone to understand an existing codebase quickly, identify the issue and deliver a clean solution without unnecessary overhead.

If you have a .NET bug, API integration or feature that needs to be shipped, send me the details and I’ll tell you how I would approach it.

Steps for completing your project

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

Delivery time starts when Rostyslav receives requirements from you.

Rostyslav works on your project following the steps below.

Revisions may occur after the delivery date.

Review the issue and provided materials

I review your description, logs, screenshots, source code, and reproduction steps.

Investigate and identify the root cause

I reproduce the problem where possible and trace the issue through the relevant code, API, database, or integration layer.

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