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Fiverr Pro
English
$
USD
I will add features and fix bugs in your existing web application
Hanif
Level 1
5.0
5.0
About this gig
Is your existing web application slow, crashing, or drowning in technical debt? Do you need a new feature added quickly by a professional?
I am a Senior Full-Stack Developer specializing in rescuing, scaling, and optimizing existing codebases. I help businesses fix their technical debt and add powerful new features to their .NET (C#) and Node.js platforms. I understand that taking over existing code is difficultI ensure I don't break your existing features while making updates.
What I Can Do For You:
- Bug Fixing: Identify and resolve critical backend and frontend errors.
- Performance Optimization: Speed up slow SQL queries and optimize API load times.
- Feature Expansion: Add new modules, dashboards, or payment gateways.
- Structural Refactoring: Clean up messy legacy code to make your app scalable.
- API Integration: Connect your app to third-party services safely.
My Tech Stack Expertise:
- ASP.NET, .NET Core, Node.js, C# (CSharp), Python, F# (FSharp), JavaScript, SQL Server, Entity Framework, PostgreSQL
Please message me BEFORE ordering so I can review your existing codebase and give you an accurate quote based on the size of the task!
Get to know Hanif
Hanif
Software Engineer : FSharp, CSharp, Dot NET
Level 1
- FromBangladesh
- Member sinceFeb 2019
- Avg. response time1 hour
- Last delivery3 months
Languages
Bengali, English
Senior Software Engineer with 5+ years of experience at a YC startup in Bangladesh, where I built scalable operational, logistics, and marketing platforms. I specialize in full-stack development, AI integration, and system optimization. I’ve mentored junior engineers and led cross-functional projects that drive business efficiency.
I’m passionate about clean architecture, performance tuning, and delivering results that exceed expectations.
My Portfolio
Other Software Development Services I Offer
FAQ
Do you need access to my server or code repository?
Yes, I will need access to your GitHub/GitLab repository and potentially your staging server environment to properly test and fix the issues without affecting your live users.
What if you can't fix the bug?
Before you place an order, I will review your codebase to ensure the fix is possible within the scope. If it requires a complete rewrite instead of a simple fix, I will inform you immediately so we can adjust the plan.
Do you work on old or legacy .NET code?
Yes, I have experience refactoring older ASP.NET applications into modern standards and migrating them to .NET Core.
Can you create documentation for the code you fix?
Yes! For my Standard and Premium packages, I include detailed inline code comments and fix documentation so your future developers understand exactly what was changed.
Will my website go down while you are fixing it?
No, I will work entirely on a local development branch or a secure staging environment. Nothing is pushed to your live production server until you thoroughly review and approve the changes.
Reviews
5 reviews for this Gig
| (5) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
Most relevant
F fatiha56
Hungary
Hanif's work in Software Development was nothing short of PROFESSIONAL. The project was completed efficiently and delivered on time, making the entire collaboration a pleasure. HIGHLY recommend! 👏
$100-$200
Price
3 weeks
Duration
Helpful?B budoya
Australia
Great work. Thanks
$100-$200
Price
5 days
Duration
Helpful?G giannisblock
Canada
kgkkjhjjkgghgk
Up to $50
Price
1 day
Duration
Helpful?G giannisblock
Canada
Really good help
$100-$200
Price
1 day
Duration
Helpful?C carlosthecan
United States
Hanif is making some minor updates to the recent project, but the task was done expertly and completed very quickly. I am always happy with the work Hanif does!
Helpful?
Reviews
5 reviews for this Gig
| (5) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
Most relevant
F fatiha56
Hungary
Hanif's work in Software Development was nothing short of PROFESSIONAL. The project was completed efficiently and delivered on time, making the entire collaboration a pleasure. HIGHLY recommend! 👏
$100-$200
Price
3 weeks
Duration
Helpful?B budoya
Australia
Great work. Thanks
$100-$200
Price
5 days
Duration
Helpful?G giannisblock
Canada
kgkkjhjjkgghgk
Up to $50
Price
1 day
Duration
Helpful?G giannisblock
Canada
Really good help
$100-$200
Price
1 day
Duration
Helpful?C carlosthecan
United States
Hanif is making some minor updates to the recent project, but the task was done expertly and completed very quickly. I am always happy with the work Hanif does!
Helpful?
