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Fiverr Pro
English
$
USD
I will fix javascript, react, angular, vue and nodejs bugs and errors
Mahfuj
About this gig
I fix bugs in JavaScript applications - frontend and backend. Runtime errors, failing APIs and performance problems.
I'm a software engineer with 5+ years of experience on production systems: ERP, CRM and SaaS platforms in daily business use. Diagnosing and repairing live applications is the core of that work, so I find the actual cause rather than patching the symptom.
FRONTEND
- JavaScript and TypeScript runtime errors
- React, Angular and Vue component, form and routing defects
- State management and RxJS problems
- Rendering and change detection issues
- Slow page loads and oversized bundles
BACKEND
- Node, Express and NestJS API errors
- Slow or failing PostgreSQL and MongoDB queries
- Authentication, session and JWT problems
- CORS, validation and integration errors
- Build and deployment failures
HOW IT WORKS
Send the repository and the error. I confirm the scope and timeline before you order, then deliver the fix with a written explanation of the root cause. If the problem turns out to be bigger than the package you picked, I tell you before starting - not halfway through.
Message me before ordering so I can confirm I can solve it.
Get to know Mahfuj
Mahfuj
Expert Frontend Engineer
- FromBangladesh
- Member sinceMay 2022
- Avg. response time1 hour
Languages
Bengali, English, Hindi, Urdu
Hi, I'm Md. Mahfujur Rahman, a full-stack web developer with 5+ years of experience building modern, scalable web applications.
I specialize in Angular and TypeScript on the frontend, and NestJS, Node.js, and PostgreSQL on the backend. I have designed and built real-world products from scratch, including Finox, a complete SaaS platform covering both frontend and backend.
I care about clean code, clear communication, and delivering on time. I am always open to collaborating on new projects.
Let's build something great together!
My Portfolio
FAQ
What if one bug turns out to be several?
That's common - one symptom often has more than one cause. I investigate before you order and tell you what I actually find. If it's bigger than the package, I send a custom offer first. I won't start the work and then ask for more money.
What do you need to debug a backend issue?
A staging or local environment I can run, plus logs and the steps to reproduce. Seeded test data is fine - I don't need your production database or live credentials.
Which frameworks do you work with?
React, Angular and Vue on the frontend, Node, Express and NestJS on the backend, with PostgreSQL or MongoDB. Plain JavaScript and TypeScript are fine too. Message me with your stack and I'll confirm.
Will you explain what was wrong?
Yes. Every delivery includes a short write-up of the root cause and exactly what I changed, so your team can learn from it.
Do you work with older versions?
Yes. Angular v12 onward, older React and Vue codebases including class components and Options API, and legacy Node projects are all fine.
What if you can't fix my problem?
I'll tell you before you order rather than take the job and fail it.
Do you sign NDAs?
Yes, happy to sign one before you share any code.
