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I will fix and improve your nextjs or react web app
Gill Hermelin
About this gig
Have an existing Next.js or React application that needs a fix or improvement?
I can help diagnose bugs, improve existing features, and make focused changes without unnecessarily rewriting your application.
I work primarily with Next.js, React, TypeScript, Node.js, PostgreSQL and Supabase, and I have experience contributing to existing production codebases as well as building full-stack applications from scratch.
I can help with:
- Next.js and React bugs
- TypeScript issues
- Responsive UI problems
- API and data-fetching issues
- Authentication and Supabase problems
- PostgreSQL and database logic
- Existing feature improvements
- Deployment and environment issues
- Code cleanup and maintainability
Please message me before ordering so I can review the scope first. Please include a brief description of the issue, your stack, and any screenshots or error messages. I'll help determine which package best fits the work.
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Get to know Gill Hermelin
Gill Hermelin
Full Stack Developer specializing in NextJS and React
- FromUnited States
- Member sinceAug 2026
- Avg. response time1 hour
Languages
English
I'm a full-stack developer with experience building and shipping production SaaS, AI-powered, and mobile products.
I work primarily with Next.js, React, TypeScript, Supabase, PostgreSQL, APIs, Vercel, and cloud deployments.
I put a strong emphasis on clean, readable architecture and clear separation of concerns, so the code I deliver is organized, maintainable, and easy for the next engineer to jump into, understand, and extend.
My Portfolio
FAQ
What types of issues can you fix?
I can help with Next.js and React bugs, TypeScript errors, responsive UI issues, API and data-fetching problems, authentication, Supabase, PostgreSQL, deployment issues, and improvements to existing features. If you're unsure whether your issue fits, message me before ordering.
Should I contact you before placing an order?
Yes. Please message me with a description of the issue, your technology stack, and any relevant screenshots or error messages. I'll review the scope and recommend the appropriate package before you order.
Can you work with an existing codebase?
Yes. Much of my development work involves understanding and improving existing applications. I focus on making targeted changes that fit the current architecture rather than unnecessarily rewriting working code.
What if you discover the problem is larger than expected?
I'll explain what I found before expanding the scope. If additional work is needed, we'll agree on the approach, cost, and timeline before I continue.
Will you deploy the fix after completing it?
Yes, if requested. I can help deploy changes to your existing environment when appropriate. Deployment can be added separately depending on your hosting setup and the scope of the work.
