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You will get bug fixes in your React, Next.js or Node.js app

Muhammad Saadullah S.Status: Offline
Muhammad Saadullah S. Muhammad Saadullah S.
5.0
Top Rated
Preview imagePreview imagePreview imagePreview imagePreview image

Let a pro handle the details

Buy Web Application Programming services from Muhammad Saadullah, priced and ready to go.
Muhammad Saadullah S.Status: Offline
Muhammad Saadullah S. Muhammad Saadullah S.
5.0
Top Rated
Preview imagePreview imagePreview imagePreview imagePreview image

Let a pro handle the details

Buy Web Application Programming services from Muhammad Saadullah, priced and ready to go.

Project details

I will fix bugs, errors, API issues, frontend problems, backend issues, deployment problems, and performance issues in your React, Next.js, Node.js, or MERN stack application.

Are you having issues with your React, Next JS, Node JS, or MERN stack application?

I can help you debug and fix frontend bugs, backend errors, API issues, database problems, deployment errors, broken UI, performance issues, authentication problems, and third-party integration bugs.

This is ideal for clients who need fast and reliable fixes without long explanations or unnecessary delays.

I can fix:

 • React component bugs
 • Next JS routing issues
 • Node JS API errors
 • Express JS backend bugs
 • MongoDB query issues
 • Authentication problems
 • API integration errors
 • Broken UI or layout issues
 • Deployment errors
 • PM2 or Nginx issues
 • Vercel deployment problems
 • Twilio, Stripe, SendGrid, or webhook issues
 • Performance and loading issues
Programming Languages
JavaScript, TypeScript
What's included
Service Tiers Starter
$50
Standard
$100
Advanced
$250
Delivery Time 1 day 3 days 5 days
Number of Revisions
123
Design Customization
-
-
-
Content Upload
-
-
-
Responsive Design
-
-
-
Source Code
-
-
-
Optional add-ons You can add these on the next page.
Extra Bug Fix (+ 1 Day)
+$50
Urgent same-day delivery
+$75
Deployment issue
+$100

Frequently asked questions

5.0
2 reviews
100% Complete
(2)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

AT

Alhanoof T.
5.00
Feb 6, 2025
MVP Website Development for Content Creation Marketplace

MI

MdToriqul I.
5.00
Sep 20, 2024
Need to Windows 10 Touchscreen Jukebox Application Great & professional work done. I would like to work long term. Thanks
Muhammad Saadullah S.Status: Offline

About Muhammad Saadullah

Muhammad Saadullah S.Status: Offline
Full-Stack Next.js | MERN Developer | React, Node.js & AI
100% Job Success
5.0  (2 reviews)
Lahore, Pakistan - 8:34 am local time
Top Rated Full-Stack Next.js | MERN Developer with 100% Job Success

I help startups and businesses build, improve, and scale production-ready SaaS web apps using Next.js, React, Node js, Express.js, MongoDB, TypeScript, Redis, Socket IO, Twilio, and AI/API integrations.

With 4+ years of production experience, I have worked with Y-Combinator backed, Misk Launchpad backed, bootstrapped startups, and independent clients across Upwork. My work includes SaaS platforms, CRMs, marketplaces, messaging systems, automation workflows, dashboards, and AI-powered web applications.

✅ Building SaaS MVPs from scratch
✅ Developing full-stack web apps using Next.js, React, Node.js, and MERN
✅ Fixing bugs and improving existing React, Next.js, and Node.js apps
✅ Adding AI agents, AI automation, OpenAI, Claude, Gemini, and DeepSeek integrations
✅ Building AI-powered chatbots, voice workflows, and backend automations
✅ Integrating Twilio, SendGrid, Stripe, Chargebee, OpenAI, and third-party APIs
✅ Building real-time apps using Socket IO, Redis, BullMQ, webhooks, and background jobs
✅ Optimizing existing codebases for performance, scalability, and maintainability
✅ Deploying apps on Vercel, AWS, GCP, Hetzner, Docker, PM2, and Nginx

Core Expertise:

👉 Frontend: Next.js, React, TypeScript, JavaScript, Tailwind CSS, Redux Toolkit
👉 Backend: Node.js, Express.js, Python, FastAPI, REST APIs, webhooks
👉 MERN Stack: MongoDB, Express.js, React, Node.js
👉 AI Integration: OpenAI API, Claude API, Gemini, DeepSeek, AI agents, prompt engineering
👉 AI Automation: LangChain, n8n, Make, Zapier, MCP servers, workflow automation
👉 Voice AI: Vapi, ElevenLabs, OpenAI Whisper, Twilio voice agents, Telnyx voice AI
👉 Databases: MongoDB, PostgreSQL, MySQL, Redis, Elasticsearch
👉 Real-Time Systems: Socket IO, WebSockets, BullMQ, background jobs, webhook processing
👉 DevOps: Docker, GCP, AWS, Hetzner, Vercel, Nginx, PM2, CI/CD

Projects:

➔ SmartAlto (YC-backed Real Estate CRM)
Worked on a production CRM platform for real estate skip tracing and lead management using React, Node.js, Express.js, MongoDB, Twilio, SendGrid, Chargebee, Docker, and GCP/GKE.

➔ Messaging SaaS Platform
Built and managed a messaging platform using Next.js, MongoDB, Redis, BullMQ, Socket IO, Twilio webhooks, PM2, Nginx, and Hetzner deployment.

➔ UGC Marketplace for Content Creators
Built a marketplace connecting content creators with businesses using Next.js, Redux Toolkit, Supabase, REST APIs, media uploads, and responsive frontend workflows.

➔ Electron Desktop Applications
Built desktop productivity and media applications using Electron, React, Tailwind CSS, local databases, and background task scheduling.

➔ AI/API Automation Workflows
Built AI-powered workflows, API integrations, automation systems, and backend services for SaaS products using Node.js, Python/FastAPI, OpenAI-style APIs, and webhook-based architectures.

What Clients Say:

"Great & professional work done. I would like to work long term. Thanks."

"He is the best person I hired on Upwork because he has good communication skills, he is patient, he maturely takes criticism and makes swift corrections, he guides you through the journey of actualizing your dream project. Lastly, I feel comfortable working with him."

Why Work With Me?

✦ Top Rated with 100% Job Success on Upwork
✦ Real production experience, not just demo projects
✦ Clear communication and regular progress updates
✦ Strong experience with SaaS, AI integrations, APIs, and real-time systems
✦ Clean, scalable, and maintainable code
✦ Startup-friendly execution with practical technical decisions

Need a reliable developer to build, fix, scale, or add AI to your SaaS product? Let’s discuss your project.

Steps for completing your project

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

Delivery time starts when Muhammad Saadullah receives requirements from you.

Muhammad Saadullah works on your project following the steps below.

Revisions may occur after the delivery date.

Share the issue details

You will share the bug description, screenshots or screen recording, steps to reproduce the issue, and access to the codebase if required.

I will review and reproduce the bug

I will check the frontend, backend, API requests, console errors, server logs, or deployment setup to understand the root cause.

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