You will get Performance Optmisation & Bug Fixing of React.js or Nextjs, Web Application
Project details
You will get a permanent fix for your React.js, Next.js, or MERN Stack web application — not a temporary patch.
With over 2 years of experience in React.js development, Next.js development, front-end development, and full-stack JavaScript development, I specialize in diagnosing and fixing complex bugs that other developers struggle to resolve, including React rendering errors, Next.js hydration mismatches, broken REST APIs, JWT authentication failures, MongoDB timeouts, Stripe webhook bugs, and TypeScript errors.
Beyond bug fixing, I optimize your entire codebase for performance — improving Core Web Vitals, achieving 90+ Lighthouse scores, reducing bundle size, and implementing lazy loading and code splitting so your app loads fast and scales confidently.
Whether you are a SaaS founder, agency, startup, or developer stuck on a critical issue, I deliver clean, fully documented fixes in just 2 to 3 days.
Message me with your bug details before ordering and I will review everything upfront — no surprises, no wasted time. Your application deserves to work perfectly.
With over 2 years of experience in React.js development, Next.js development, front-end development, and full-stack JavaScript development, I specialize in diagnosing and fixing complex bugs that other developers struggle to resolve, including React rendering errors, Next.js hydration mismatches, broken REST APIs, JWT authentication failures, MongoDB timeouts, Stripe webhook bugs, and TypeScript errors.
Beyond bug fixing, I optimize your entire codebase for performance — improving Core Web Vitals, achieving 90+ Lighthouse scores, reducing bundle size, and implementing lazy loading and code splitting so your app loads fast and scales confidently.
Whether you are a SaaS founder, agency, startup, or developer stuck on a critical issue, I deliver clean, fully documented fixes in just 2 to 3 days.
Message me with your bug details before ordering and I will review everything upfront — no surprises, no wasted time. Your application deserves to work perfectly.
Programming Languages
HTML & CSS, JavaScript, TypeScriptCoding Expertise
Cross Browser & Device Compatibility, Performance Optimization, SecurityWhat's included $50
These options are included with the project scope.
$50
- Delivery Time 1 day
- Number of Revisions Unlimited
Optional add-ons
You can add these on the next page.
Design Customization
(+ 2 Days)
+$20
Responsive Design
(+ 2 Days)
+$10
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AH
Ali H.
Mar 1, 2026
React MERN Stack Developer for SaaS Web App Updates
Danyal is an extremely talented and professional developer. He delivered high-quality work within the deadline, communicated clearly throughout the project, and handled everything smoothly. I’m very impressed with his skills and would absolutely work with him again.
RE
Remy E.
Feb 11, 2026
React/Next.js Developer Needed to Fix AI Job Tracker SaaS
We had major authentication and routing issues in our MERN app. Danyal quickly identified the root cause and refactored the logic cleanly.
About Danyal
React & Next.js Frontend Developer | Building Fast, Scalable SaaS MVPs
100%
Job Success
Islamabad, Pakistan - 5:43 am local time
⚡ Building modern, scalable and performant SaaS MVPs⚡
I build scalable SaaS products, high-performance web apps, and startup MVPs using reactjs and nextjs.
🏆 99% Success Rate
🔥 30+ successfully delivered projects
⭐ Apps serving 10,000+ users
💰 Products generating real business revenue
As a Frontend React Developer and Full Stack Developer React Node, I help founders and startups transform ideas into fast, scalable, and revenue-generating products.
Whether you need:
✔ React Developer
✔ Next.js Developer
✔ Frontend Developer React
✔ Full Stack Developer React Node
✔ MERN Stack Developer
✔ SaaS MVP Developer
I can take your product from idea → MVP → scalable platform.
🚀 Results I've Delivered
✔ Built a SaaS analytics dashboard that reduced manual reporting by 70%, saving teams 200+ hours/month
✔ Developed Next.js applications achieving 90+ Lighthouse performance scores and 2–3x SEO traffic growth
✔ Built a marketplace platform with Stripe billing reducing checkout drop-off by 25%
✔ Implemented Supabase real-time systems across 5+ production SaaS apps
✔ Engineered APIs processing 1M+ requests/month with 99.9% uptime
✔ Integrated AI features using OpenAI & LLMs reducing manual work by 40–50%
✔ Improved frontend performance 2–3x faster load times
💻 Technical Stack
• Frontend Development
React.js · Next.js · TypeScript · JavaScript · Redux · Zustand · RTK Query · Tailwind CSS · Material UI · HTML5 · CSS3
• Backend Development
Node.js · Express.js · NestJS · Python · Django
• Databases
PostgreSQL · MongoDB · MySQL · Supabase · Firebase · Redis
• AI & Integrations
OpenAI · ChatGPT · LangChain · Stripe · Twilio · REST APIs · GraphQL
• DevOps & Deployment
AWS · Docker · Vercel · Netlify · CI/CD · GitHub Actions
What I Build
As a React Developer and Full Stack Developer, I specialize in building:
✔ SaaS platforms
✔ Startup MVPs
✔ Dashboards & Admin Panels
✔ Marketplaces
✔ AI-powered web applications
✔ Stripe subscription platforms
✔ Real-time apps with Supabase
✔ High-performance Next.js websites
Industries:
SaaS · FinTech · HealthTech · EdTech · E-commerce · Real Estate · Logistics · AI Startups
⚙️ How I Work
Every project starts with a short discovery phase where we align on:
• Product architecture
• timeline & milestones
• technical stack
• scalability plan
I focus on clean architecture, performance optimization, and long-term maintainability.
I don't just write code — I help businesses ship products faster and scale confidently.
🤝 Let's Build Something Great
If you're looking for a React Developer, Next.js Developer, or Full Stack Developer React Node who can deliver fast MVPs and scalable products, let's talk.
Send me a message with your project details and I'll respond with a clear plan and honest feedback.
Let's build something amazing Together.
React Developer | React.js Developer | Frontend React developer | Frontend developer react.js | Frontend developer tailwindCSS | Next.js Developer | Frontend Developer React | Full Stack Developer React Node | MERN Stack Developer | JavaScript Developer | TypeScript Developer | SaaS Developer | Web Application Developer | Dashboard Developer | Marketplace Developer | Stripe Integration | Supabase Developer | AI Web Developer | ChatGPT Integration | OpenAI Developer
Steps for completing your project
After purchasing the project, send requirements so Danyal can start the project.
Delivery time starts when Danyal receives requirements from you.
Danyal works on your project following the steps below.
Revisions may occur after the delivery date.
Audit & Diagnose
You tell me the issues you are facing and I clone your repo, reproduce every bug, and run a full codebase audit to identify root causes — not just symptoms — and document a clear fix plan before writing a single line of code.
Fix, Optimize & Test
I implement all bug fixes using clean best practices, optimize performance, bundle size, and Core Web Vitals, then test everything across browsers, devices, and environments end-to-end.