I will fix your backend bug or API issue


About this gig
Your API is broken and you don't have time to dig through it yourself.
I do.
I'm a backend developer with 5+ years of experience working with
Node.js, Python, Go, Java, and C#. I fix bugs fast, explain what
caused them, and make sure they don't come back.
WHAT I FIX:
API endpoints returning wrong data or crashing
Authentication/authorization issues (JWT, OAuth, sessions)
Database query bugs (Postgres, MySQL, MongoDB)
Integration failures (third-party APIs, webhooks, payment gateways)
Performance issues (slow endpoints, N+1 queries)
Deployment/environment bugs
HOW IT WORKS:
1. Send me your repo (GitHub/GitLab) or relevant code + error logs
2. I diagnose the issue and give you a quick estimate of time needed
3. I fix it, test it, and explain what went wrong
4. You review and confirm
WHY WORK WITH ME:
I don't just patch the symptom I find the actual root cause so
the bug doesn't come back in a different form next week. You'll
get a short explanation of what broke and why, in plain language.
Send me a message with details before ordering if your case is
unusual or the bug is hard to describe happy to take a quick
look for free to confirm I can help.
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Get to know Agustin O.
High Performance Web and Desktop Software Engineer
- FromArgentina
- Member sinceAug 2026
Languages
Spanish, English
My Portfolio
FAQ
Do I need to give you full access to my codebase?
No, send only the relevant files/repo section, or a private repo invite. I sign an NDA if needed.
What if the bug takes longer than the package hours?
I'll tell you before going over, no surprise charges. We agree on next steps together.
What info do you need from me to start?
Error logs/stack trace, steps to reproduce, and access to the relevant code (repo link or files).
