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You will get React and Next.js bug fixes with clean production-ready code

Vasyl P.Status: Offline
Vasyl P. Vasyl P.
5.0
Rising Talent
Preview imagePreview imagePreview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Vasyl, priced and ready to go.
Vasyl P.Status: Offline
Vasyl P. Vasyl P.
5.0
Rising Talent
Preview imagePreview imagePreview image

Let a pro handle the details

Buy Web Programming Bug Fixes services from Vasyl, priced and ready to go.

Project details

Is your React or Next.js app broken, buggy, slow, or full of messy code?

I will help you fix bugs, clean up bad code, repair API integrations, resolve TypeScript errors, and make your web app more stable and production-ready.

This project is perfect if your previous developer disappeared, your AI-generated code is unstable, your app has bugs before launch, or your project works locally but fails in production.

I can help with React bugs, Next.js issues, TypeScript errors, API problems, authentication bugs, Stripe integration issues, Tailwind CSS layout problems, deployment errors, and messy code cleanup.

I work with React, Next.js, TypeScript, JavaScript, Node.js, NestJS, Prisma, MongoDB, PostgreSQL, Tailwind CSS, Stripe, Vercel, VPS, PM2, and Nginx.

Before starting, I will review your issue and confirm what can be fixed within the selected package.
Programming Languages
JavaScript
Coding Expertise
Cross Browser & Device Compatibility, Performance Optimization, Security
What's included
Service Tiers Starter
$90
Standard
$220
Advanced
$500
Delivery Time 2 days 4 days 7 days
Number of Revisions
122
Bug Investigation
Fix Documentation
-
Detailed Code Comments
-
-
Optional add-ons You can add these on the next page.
Additional Revision
+$40

Frequently asked questions

5.0
3 reviews
100% Complete
(3)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)
1% Complete
(0)

WM

William M.
5.00
Jul 21, 2026
Fix a Small TypeScript Issue in a Next.js Component Very professional work; all fixes were made very quickly

SL

San L.
5.00
Mar 19, 2025
Coding Front-End SaaS I had the pleasure of working with Vasyl P. on a frontend project, and I couldn’t be more satisfied with the results. He delivered high-quality, well-structured, and responsive code, ensuring a seamless user experience.

Communication was excellent throughout the project—Vasyl P. was always responsive, proactive, and open to feedback. He not only met all the requirements but also suggested valuable improvements that enhanced the final product.

If you’re looking for a skilled, reliable, and detail-oriented frontend developer, I highly recommend Vasyl. I would definitely work with him again in the future!

SL

San L.
5.00
Nov 8, 2024
Coding Front-End SaaS Great experience working with Vasyl! He delivered high-quality code on time, communicated effectively, and showed excellent technical skills. Highly recommended for anyone in need of a reliable programmer!
Vasyl P.Status: Offline

About Vasyl

Vasyl P.Status: Offline
Senior Full Stack Developer React Next.js NestJS | AI SaaS Developer
100% Job Success
5.0  (3 reviews)
Chernivtsi, Ukraine - 11:26 am local time
Senior Full Stack Developer specializing in Next.js, NestJS, React, Node.js, TypeScript, SaaS development, AI integrations, Stripe, and React Native. I build production-ready apps, fix existing applications, complete AI-generated web apps, and scale SaaS products.

🏆 12+ years in JavaScript and TypeScript development
✅ 45+ web and mobile products delivered
✅ Full-cycle SaaS development from architecture to deployment
✅ Experience with EdTech, eCommerce, CRM, marketplaces, payments, AI SaaS, and mobile apps

2,600+ completed orders and 520+ registered customers supported through an eCommerce and CRM platform built with Next.js, React, Node.js, and TypeScript.

90% faster order processing and up to 80% less manual work through workflow automation, API integrations, and React admin dashboard improvements.

10+ React Native applications delivered for iOS and Android with authentication, payments, notifications, API integrations, and production releases.

✅ SENIOR FULL STACK DEVELOPER SERVICES

As a Senior Full Stack Developer, I build new SaaS MVPs, join existing teams, rescue unfinished applications, fix production bugs, add features, refactor legacy code, and prepare AI-generated applications for launch.

As a Next.js Developer, I build SaaS applications, dashboards, admin panels, customer portals, marketplaces, SSR applications, and responsive interfaces using Next.js App Router, React, TypeScript, Tailwind CSS, TanStack Query, Zustand, Redux, and React Hook Form.

As a NestJS Developer and Node.js Developer, I build REST APIs, authentication, RBAC, multi-tenant SaaS architecture, background jobs, WebSocket features, payment systems, file processing, automation, and secure backend services.

As a React Developer, I create reusable components, forms, tables, dashboards, responsive layouts, and maintainable frontend architecture.

As a React Native Developer, I develop iOS and Android applications with APIs, authentication, subscriptions, push notifications, analytics, and store deployment.

✅ SAAS DEVELOPMENT

I work on SaaS MVP development, Full Stack SaaS development, B2B SaaS platforms, multi-tenant SaaS applications, AI SaaS products, EdTech SaaS platforms, fintech applications, eCommerce systems, CRM platforms, booking products, marketplaces, admin panels, and internal tools.

I take SaaS products from architecture and database design through frontend, backend, testing, deployment, scaling, and support.

✅ AI DEVELOPMENT AND AI INTEGRATIONS

As an AI Developer and AI SaaS Developer, I integrate OpenAI API, Claude API, LLM features, AI chatbots, AI content generation, document processing, PDF processing, classification, structured outputs, prompt engineering, automated workflows, and AI usage tracking.

I also fix and complete AI-generated web applications created with Cursor, Claude Code, ChatGPT, Lovable, Bolt, or similar AI development tools.

I can audit an AI-generated codebase, fix TypeScript errors, repair frontend and backend logic, complete missing features, remove duplicated code, secure APIs, optimize performance, connect databases, integrate third-party APIs, and prepare the application for production deployment.

✅ STRIPE AND PAYMENT DEVELOPMENT

As a Stripe Developer, I implement Stripe Checkout, Stripe subscriptions, recurring billing, Payment Intents, Stripe Connect, customer portals, pricing plans, trials, invoices, webhooks, and subscription lifecycle management.

I fix failed Stripe webhooks, broken checkout flows, incorrect subscription states, duplicate payments, and database synchronization problems.

✅ BUG FIXING AND EXISTING APPLICATIONS

I provide Next.js bug fixing, React bug fixing, TypeScript error fixing, NestJS API development, Node.js backend development, Vercel deployment fixes, production bug fixing, performance optimization, Prisma and MongoDB fixes, PostgreSQL query optimization, authentication fixes, feature development, code refactoring, legacy codebase stabilization, and AI-generated app completion.

I preserve existing behavior where required, understand the business logic before changing code, and avoid quick fixes that create new technical debt.

✅ TECHNOLOGY STACK

Frontend: Next.js, React, React Native, TypeScript, Tailwind CSS, Redux, Zustand, TanStack Query, React Hook Form.

Backend: NestJS, Node.js, Express.js, REST API, WebSocket, Prisma ORM, PostgreSQL, MongoDB, MySQL, Firebase.

AI and Payments: OpenAI API, Claude API, AI agents, LLM integrations, Stripe, third-party APIs, PDF and file processing.

DevOps: AWS, Vercel, Ubuntu, Nginx, PM2, GitHub Actions, CI/CD, production deployment.

You can hire me as a Senior Full Stack Developer, Next.js Developer, NestJS Developer, React Developer, Node.js Developer, TypeScript Developer, SaaS Developer, AI Developer, Stripe Developer, or React Native Developer.

Send me your requirements, repository, technical problem, or unfinished AI-generated application. I will help you build, fix, complete, launch, or scale it

Steps for completing your project

After purchasing the project, send requirements so Vasyl can start the project.

Delivery time starts when Vasyl receives requirements from you.

Vasyl works on your project following the steps below.

Revisions may occur after the delivery date.

Step 1

Review requirements and reproduce the issue

Step 2

Investigate the codebase, errors, API flow, and project setup

Review the work, release payment, and leave feedback to Vasyl.