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$
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I will fix python fastapi backend bugs and API errors
Antonio
About this gig
Is your FastAPI backend returning errors, failing to start or behaving unexpectedly? I will investigate and fix clearly defined issues in an existing Python backend.
I can help with:
FastAPI startup and runtime errors
HTTP 500 errors and broken endpoints
Request validation and Pydantic issues
REST API and third-party integration errors
Database connection and query problems
Authentication, CORS and configuration issues
Async or background-task failures
Docker and dependency problems
Focused regression tests for the corrected behavior
You will receive the corrected source code and a clear explanation of the cause and solution. Standard and Premium packages include additional testing and documentation.
Please provide the source code, error logs, reproduction steps and expected behavior. Remove production secrets, passwords and private customer data before sharing files.
This Gig covers debugging and repairing an existing codebase. New applications, major feature development, complete rewrites, production deployment and unrelated additional bugs require a custom offer.
Please message me before ordering if you are unsure which package matches your issue.
Get to know Antonio
Antonio
Python Backend Applied AI Developer
- FromBrazil
- Member sinceSep 2023
- Avg. response time1 hour
Languages
English, Portuguese, Spanish
Python backend and applied AI developer focused on practical, maintainable solutions. I build and troubleshoot FastAPI and Flask APIs, RAG pipelines, local LLM applications, chatbots and Python automations. My portfolio includes a medical RAG assistant, an AI helpdesk triage API and a local coding assistant with OAuth. I value clear scope, readable code, automated tests, documentation and honest communication.
My Portfolio
FAQ
Q: What counts as one bug?
A: One bug is a single reproducible problem with a defined expected behavior, such as one failing endpoint, startup error or database connection issue. Multiple unrelated errors require a larger package or custom offer.
Q: What do you need to begin?
A: I need the relevant source code, dependency files, error logs, reproduction steps and expected behavior. Please remove passwords, API keys, production secrets and private customer data before sending anything.
Q: Can you guarantee that every issue will be fixed?
A: I will investigate the issue thoroughly and fix it when the cause is within the provided code and package scope. If the problem comes from an unavailable third-party service or missing access, I will document the cause and recommend the next steps.
Q: Will you add tests for the fix?
A: Focused regression tests are included in the Standard and Premium packages. For the Basic package, testing can be added as an extra when appropriate.
Q: Does this Gig include new features or deployment?
A: This Gig focuses on debugging an existing Python or FastAPI backend. New features, complete applications, major rewrites and production deployment require a custom offer after reviewing the requirements.
