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I will fix next js bug, react error, node js, express, and database issues
Mehedi Hassan
Level 1
About this gig
Are production bugs, server crashes, hydration errors, or database failures blocking your release?
A broken app stalls launches, ruins UX, and burns time. As a Full-Stack Engineer, I diagnose and permanently fix issues across your entire JavaScript/TypeScript stack.
What I Resolve Across Your Stack: Next.js & React: App Router boundary errors ("use client"), SSR hydration mismatches, Server Actions, state loops, and Tailwind UI glitches. Node.js & Express: Middleware crashes, CORS blocking, async exceptions, and broken REST API endpoints. Databases (MongoDB, MySQL, PostgreSQL): Query deadlocks, Mongoose leaks, schema migration errors, and ORM issues (Prisma, Drizzle). Auth & Security: JWT token refresh failures, NextAuth/Auth.js session bugs, OAuth callbacks, and security headers. Deployment & CI/CD: Vercel, Render, AWS, and Docker build pipeline failures. AI Code Refactoring: Fixing & stabilizing fragile AI-generated code bases.
Why Me? Clean TypeScript code, zero regressions, enterprise security practices, and optional Loom video root-cause walkthroughs.
Please message me with your repository access or error logs before ordering!
Get to know Mehedi Hassan
Mehedi Hassan
Work First, Pay later
Level 1
- FromBangladesh
- Member sinceJul 2021
- Avg. response time1 hour
- Last delivery2 weeks
Languages
Bengali, English
👋 Hey there! I’m Mehedi Hassan – a passionate Full Stack Developer with hands-on experience in MERN stack (MongoDB, Express.js, React.js, Node.js), WordPress development, and custom web solutions. I specialize in building high-performance websites, web apps, that are fast, modern, and scalable.
Other Software Development Services I Offer
FAQ
Should I contact you before placing an order?
Yes, sending a direct message before ordering is strongly encouraged. Reviewing your repository, backend error logs, and reproduction steps beforehand ensures an accurate diagnosis and allows for a custom offer tailored precisely to your scope.
What information is required to begin debugging?
You will need to provide repository access (GitHub, GitLab, Bitbucket), clear step-by-step instructions to reproduce the bug, terminal/browser error logs, and non-sensitive staging environment variables (including sandbox database keys)
Do you handle both SQL (MySQL/PostgreSQL) and NoSQL (MongoDB) databases?
Yes. Comprehensive support is provided for MongoDB (Mongoose), PostgreSQL, and MySQL, including ORM debugging with Prisma, Drizzle, and Sequelize.
Do you specialize in Next.js 14 and Next.js 16 App Router issues?
Yes. The service natively supports modern Next.js features, including the App Router directory structure, React Server Components, Server Actions, edge middleware, and revalidation caching strategies.
Can you fix bugs in full-stack codebases generated by AI tools like Bolt, Codex, or Claude?
Yes. Full-stack applications built via AI code generators often suffer from state synchronization flaws, broken database schemas, and unhandled Express route crashes. These codebases are systematically analyzed, patched, and refactored for production stability.
What happens if a bug cannot be resolved?
If an issue cannot be reproduced due to third-party API outages or external cloud provider failures outside repository control, detailed diagnostic documentation is supplied. If a technical solution cannot be delivered within the framework scope, a mutual cancellation is processed promptly.
