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You will get I will fix bugs in your React/Node.js application

Umar A.Status: Offline
Umar A. Umar A.
5.0
Preview image

Let a pro handle the details

Buy Custom Website Programming services from Umar, priced and ready to go.
Umar A.Status: Offline
Umar A. Umar A.
5.0
Preview image

Let a pro handle the details

Buy Custom Website Programming services from Umar, priced and ready to go.

Project details

I provide professional bug fixing and code review services for React, Next.js, Node.js, NestJS, and full stack applications. Whether it’s a single bug, multiple issues, or a complete code audit, I quickly identify the root cause and implement clean, tested solutions.

I specialize in fixing JavaScript/TypeScript errors, React component issues, API failures, authentication problems, database query errors, performance bottlenecks, and deployment mistakes. Beyond just fixing bugs, I offer detailed reports, best practice recommendations, and optional code review to prevent future issues.

With experience across full stack projects, you get a reliable, professional developer who communicates clearly, delivers fast, and ensures your code runs smoothly and securely.
Programming Languages
JavaScript, TypeScript
Coding Expertise
Performance Optimization, Security
What's included
Service Tiers Starter
$50
Standard
$150
Advanced
$400
Delivery Time 1 day 3 days 5 days
Number of Revisions
123
Number of Pages
15
Design Customization
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-
Content Upload
-
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-
Responsive Design
-
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Source Code
-
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Optional add-ons You can add these on the next page.
Fast Delivery
+$50 - $100
Additional Revision
+$30
Additional Module / Feature Fix (+ 1 Day)
+$40
Performance Optimization (+ 2 Days)
+$60

Frequently asked questions

5.0
1 review
100% Complete
(1)
1% Complete
(0)
1% Complete
(0)
1% Complete
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1% Complete
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MS

Muhammad S.
5.00
Mar 1, 2026
Optimize MongoDB Queries & Express.js Backend Great work! Umar optimized our MongoDB queries and boosted our app speed. He explained the fixes clearly and was professional throughout the process. Highly recommended for any performance improvements!
Umar A.Status: Offline

About Umar

Umar A.Status: Offline
Senior MERN Stack Developer | Next.js, NestJS, PostgreSQL, MongoDB
5.0  (1 review)
Lahore Cantt, Pakistan - 8:23 am local time
✔ 5+ years of professional experience as a Senior MERN Stack Developer
✔ 10k+ active users supported with scalable and reliable systems
✔ High-traffic applications built to handle concurrent users smoothly
✔ 60-80% faster performance through API & frontend optimization
✔ 15+ production systems secured with authentication & RBAC
✔ 60-70% reduced maintenance costs with clean, production-ready code

Hi, I’m Umar Afzal. With 5+ years of professional experience, I have successfully delivered 20+ MERN stack projects for startups and enterprises, helping them scale their web applications for thousands of users. I have built secure authentication and RBAC systems across 15+ live platforms, optimized APIs and frontend performance to improve load times by 60–80%, and implemented robust database designs for both MongoDB and PostgreSQL. My work consistently helps clients reduce maintenance costs, accelerate development, and achieve measurable growth, while ensuring high-quality, scalable, and maintainable code.

Frontend: React.js, Next.js, TypeScript, Tailwind CSS, HTML5, CSS3, JavaScript (ES6+), Responsive UI/UX Design
Backend: Node.js, NestJS, Express.js, RESTful APIs, Server-side Architecture, Authentication & Authorization (JWT, OAuth)
Databases: MongoDB, PostgreSQL, Mongoose, Query Optimization, Data Modeling
Cloud & Integrations: AWS S3, Google Drive API, OneDrive, Dropbox, Twilio (SMS/OTP), Payment Gateways, Third-party API Integration
Tools & DevOps: Git, GitHub, GitLab, CI/CD Pipelines, Docker, Testing (Jest, Cypress), Linting & Code Quality

If you’re looking for a reliable full-stack developer who delivers clean, scalable, and high-performance solutions, let’s connect. Send me a message with your requirements, and I’ll help you turn your idea into a solid, production-ready application.

Steps for completing your project

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

Delivery time starts when Umar receives requirements from you.

Umar works on your project following the steps below.

Revisions may occur after the delivery date.

Requirement Analysis

Review provided code and bug description.

Code Investigation

Identify root cause and dependencies.

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