Upwork home
Sign up
Project Catalog
DesignDesign
Video & AudioVideo & Audio
Development & ITDevelopment & IT
MarketingMarketing
Writing & TranslationWriting & Translation
MoreMore

You will get your react, nextjs or nodejs application bug fixed

Muhammad O.Status: Offline
Muhammad O.
Preview image

Let a pro handle the details

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

Let a pro handle the details

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

Project details

Facing bugs in your React, Next.js, or Node.js application?
I will quickly identify and fix bugs without breaking your architecture.

I can help with:
 • React UI bugs
 • Next.js SSR issues
 • API errors
 • Database connection problems
 • Authentication issues
 • Deployment errors
 • Performance optimization

Tech stack I work with:
 • React.js
 • Next.js
 • Node.js
 • Express / Fastify
 • MySQL / MongoDB

Why work with me?
 • 4+ years experience
 • Clean debugging process
 • Secure & scalable fixes
 • Clear communication

Please message before ordering for large issues.
Programming Languages
JavaScript, Python, TypeScript
Coding Expertise
Performance Optimization, Security, Design
What's included
Service Tiers Starter
$10
Standard
$40
Advanced
$80
Delivery Time 2 days 4 days 6 days
Number of Revisions
123
Bug Investigation
Fix Documentation
Detailed Code Comments

Frequently asked questions

Muhammad O.Status: Offline

About Muhammad

Muhammad O.Status: Offline
Senior Fintech & Full-Stack Engineer | SaaS, Node.js, Next.js, Python
Karachi, Pakistan - 4:12 am local time
I help startups, founders, and businesses build secure, scalable web applications and APIs using modern full-stack and Python technologies.

I’m a Senior Full-Stack Engineer with 4+ years of experience building production-grade systems, including fintech platforms serving 50,000+ users.

I work across both JavaScript and Python ecosystems.

What I specialize in:

• SaaS MVP development
• Fintech & payment systems
• REST API architecture
• FastAPI & Python backend development
• Next.js & React frontend applications
• Secure authentication (JWT, OAuth2)
• Payment gateway integrations
• Performance optimization & debugging

Tech Stack:

Frontend:
Next.js, React.js, Tailwind CSS, TypeScript

Backend:
Node.js, Express, Fastify
Python, FastAPI
MySQL, PostgreSQL, MongoDB

Other:
JWT, OAuth, Redis, Docker, Cloud Deployment

I can help you with:

✅Building full SaaS platforms
✅Developing secure APIs in Node.js or FastAPI
✅Fixing backend or frontend bugs
✅Optimizing slow queries
✅Adding new features to existing apps
✅Integrating third-party APIs

If you need clean architecture, scalable code, and someone who understands both business logic and system design — let’s talk.

Steps for completing your project

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

Delivery time starts when Muhammad receives requirements from you.

Muhammad works on your project following the steps below.

Revisions may occur after the delivery date.

Requirements

Client provide requirements and I start working

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