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Fiverr Pro
English
$
USD
I will fix react and nextjs bugs with tested code and clear handover
Jonathan G
About this gig
A broken form, React state issue or Next.js error can block your release. I will investigate and fix clearly scoped bugs in your existing React or Next.js application.
I have 4+ years of professional development experience across agency and financial-services teams. My focus is a maintainable fix with clear verification.
Packages cover 1, 3 or 5 agreed small bugs. A small bug is one reproducible defect with a local fix in up to 3 existing source files; it does not require a new feature or architecture change. Standard covers one user flow; Premium covers up to two.
Every delivery includes the changed source code, a root-cause summary and steps to verify the fix. Standard and Premium also include regression checks as agreed.
Please message me with the error, reproduction steps and stack before ordering. I will confirm scope without asking for production passwords.
Full app rebuilds, security audits, database recovery and emergency on-call support are excluded. I work in English and German.
Get to know Jonathan G
Jonathan G
React Nextjs and TypeScript Developer
- FromGermany
- Member sinceAug 2019
Languages
English, German, Chinese, Korean
I'm Jonathan, a German fullstack developer with 4+ years of professional experience in agency and financial-services teams. I build and maintain web applications with React, Next.js and TypeScript. I can help you fix frontend bugs, connect Sanity CMS, migrate JavaScript to TypeScript, or build a document chatbot with source citations. You receive maintainable code, testing notes and a clear handover. I work in German and English and am based in South Korea. Send me your requirements so we can agree on a practical scope.
Other Software Development Services I Offer
FAQ
What qualifies as a small bug?
One reproducible defect with a local fix in up to 3 existing source files. Basic covers 1 bug; Standard up to 3 in one flow and 8 files; Premium up to 5 in two flows and 12 files. A new feature, architecture change or major upgrade needs separate scoping.
Can you fix an AI-generated application?
Yes, if it is an accessible React or Next.js codebase that runs locally. The same scope limits apply. I cannot promise a complete rescue or rebuild under a small bug package.
What testing is included?
Basic includes before/after reproduction. Standard adds 2 agreed regression checks; Premium adds 3. I use your existing automated test setup where suitable, otherwise documented manual checks. Building a new whole-app test suite is excluded.
Can you repair authentication or payment problems?
A local frontend integration defect may fit after review. Changes to identity architecture, financial transaction logic, permissions or security controls require a separately scoped engagement.
What if my issue is bigger than the package?
Please message me first so I can assess fit. If an order reveals a material scope mismatch, I will explain it promptly and agree a revised scope, custom offer or resolution through Fiverr before doing extra work.
What counts as a revision?
One revision is one consolidated feedback round on the agreed deliverable. It does not add pages, features or integrations. New scope needs a separate quote. Report defects in my delivered changes within 7 days of completion for correction; unrelated changes are excluded.
Do I receive source code and are ongoing costs included?
Source code and setup notes are included. Hosting, domains, paid assets, CMS plans and AI or other API usage are paid by you. Third-party libraries retain their licenses. Use your own service accounts; do not send passwords or secret API keys in chat.
Do you use AI development tools?
I may use AI coding tools to assist development, and I remain responsible for reviewing and testing the delivery. Tell me about AI restrictions before ordering. I will agree the handling of confidential code or documents with you before using external AI services.
How will we communicate?
I work in English and German and am based in South Korea. Please use Fiverr messages for project scope, updates and approvals. Repository access is only for delivery. Calls are by appointment through Fiverr where available, with a written handover as the default.
