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$
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I will fix bugs in your node js python or dotnet backend and API
Cong Cuong
5.0
5.0
About this gig
I debug and fix backend and API issues in Node.js, Python, and .NET/C#. You get the fix AND a plain English explanation of what actually went wrong.
WHAT I FIX
- APIs returning errors, wrong data, or nothing at all
- Authentication, JWT, session and CORS bugs
- Database issues: slow queries, deadlocks, failed migrations
- Broken integrations: payments, webhooks, OAuth, email
- "Works on my machine" deployment and environment bugs
- Memory leaks, timeouts, race conditions
STACK
Node.js (Express, NestJS), Python (FastAPI, Django, Flask), C#/.NET Core, SQL Server, PostgreSQL, MySQL, MongoDB, Docker
WHY ME
- 6+ years debugging real production systems under real pressure
- You get a root-cause explanation, not just a patched file
HOW IT WORKS
1. Message me the error, your stack, and repo access
2. I confirm I can fix it and quote you BEFORE you pay
3. You order, I fix, you get the fix plus prevention advice
Get to know Cong Cuong
Cong Cuong
Full Stack Developer: DotNET, Nodejs, React, DevOps
- FromVietnam
- Member sinceJan 2024
- Avg. response time6 hours
- Last delivery1 year
Languages
English, Vietnamese
I'm a full-stack developer with 6+ years building production systems in healthcare, education and business management.
I work across the whole stack — .NET, Python, Node.js, React, Angular, SQL Server, PostgreSQL — and handle everything from database design and architecture to deployment and monitoring.
Whether you need a system built from scratch, a new feature, a bug fixed or a slow app made fast, I'll propose the approach that actually fits your needs.
My Portfolio
Other Software Development Services I Offer
FAQ
I'm not sure which package I need. What do I do?
Message me first. Send the error message and your stack, and I'll tell you honestly which package covers it. If it's smaller than you thought, I'll say so.
Do you need access to my repository?
Yes, for most bugs. GitHub/GitLab collaborator access is ideal. A zip works too. I'm happy to sign an NDA.
What if you can't fix it?
I check feasibility before you order, so this is rare. If I take the order and genuinely can't solve it, I'll cancel and you get a full refund.
Reviews
1 reviews for this Gig
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Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
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R randy0116
Singapore
Cong Cuong truly impressed with a flawless and well-documented delivery that showcased exceptional professionalism. Working with him was a breeze, given his quick responsiveness and excellent language fluency. He consistently went above and beyond, making the entire experience delightful! 🙌
$200-$400
Price
12 days
Duration
C 
Seller's Response
Helpful?
Reviews
1 reviews for this Gig
| (1) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Quality of delivery
- Value of delivery
Sort By
Most relevant
R randy0116
Singapore
Cong Cuong truly impressed with a flawless and well-documented delivery that showcased exceptional professionalism. Working with him was a breeze, given his quick responsiveness and excellent language fluency. He consistently went above and beyond, making the entire experience delightful! 🙌
$200-$400
Price
12 days
Duration
C Seller's Response
Helpful?
