I will fix and optimize your react, nextjs and nodejs application

D
deniman78
D
deniman78
Denis

About this gig

Is your React, Next.js, or Node.js application throwing errors, crashing, or not behaving the way it should? I can help.

I'm a full-stack developer specializing in React, Next.js, and Node.js. I fix bugs fast, without breaking anything else in the process. Whether it's a broken UI component, a failing API call, a state management issue, a server crash, or a console error nobody can explain, I'll track down the root cause and fix it properly, not just patch the symptom.

What I can fix:

  • Frontend bugs (React/Next.js): broken components, layout issues, state bugs, routing problems, hydration errors
  • Backend bugs (Node.js): API errors, server crashes, database connection issues, auth problems
  • Console errors, warnings, and unexpected behavior
  • Deployment and build errors
  • Performance and slow-loading issues

How it works:

  1. Send me your code (GitHub repo, ZIP, or project access)
  2. Describe the bug(s) screenshots, error messages, or steps to reproduce help a lot
  3. I diagnose and fix it, testing thoroughly before delivery
  4. You get a clear explanation of what was wrong and how I fixed it

Clean fixes, honest timelines, fast communication. Message me first if you're unsure which package fits your issue!

Get to know Denis

Denis

Senior Full Stack Developer

  • FromUkraine
  • Member sinceJun 2026
  • Avg. response time1 hour
  • Languages

    English, Ukrainian, Russian
I’m a Senior Full-Stack Developer with 8+ years of professional experience building modern, scalable, and high-performance web applications. I specialize in React, Next.js, Node.js, and NestJS, with hands-on experience integrating AI-powered features and modern AI solutions into web applications. I focus on clean architecture, maintainable code, performance, and delivering reliable solutions tailored to business needs. Clear communication, attention to detail, and high-quality results are my priorities.

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