You will get React code refactoring and Next.js codebase stabilization
Top Rated
Project details
I provide React code refactoring and Next.js codebase stabilization for applications that have become difficult to maintain, slow to extend, or unreliable. This can include AI-generated or rapidly built code, technical debt, duplicated logic, unstable state management, unnecessary re-renders, weak TypeScript coverage, and components that have grown too large.
What this project can include:
• restructuring React components and extracting reusable logic
• improving TypeScript types and data contracts
• cleaning up Zustand, Redux, or Context state
• reducing unnecessary re-renders and performance bottlenecks
• improving frontend architecture without changing expected behavior
• preparing the codebase for safer long-term feature development
I work with React, Next.js, TypeScript, JavaScript, Zustand, Redux, TanStack Query, Tailwind CSS, and API integrations.
The goal is a cleaner, more predictable codebase that is easier to understand, test, and extend. Please message me before ordering if the application needs a full rewrite, major backend changes, or work outside the selected package.
What this project can include:
• restructuring React components and extracting reusable logic
• improving TypeScript types and data contracts
• cleaning up Zustand, Redux, or Context state
• reducing unnecessary re-renders and performance bottlenecks
• improving frontend architecture without changing expected behavior
• preparing the codebase for safer long-term feature development
I work with React, Next.js, TypeScript, JavaScript, Zustand, Redux, TanStack Query, Tailwind CSS, and API integrations.
The goal is a cleaner, more predictable codebase that is easier to understand, test, and extend. Please message me before ordering if the application needs a full rewrite, major backend changes, or work outside the selected package.
Programming Languages
JavaScript, TypeScriptCoding Expertise
Performance OptimizationWhat's included
| Service Tiers |
Starter
$150
|
Standard
$650
|
Advanced
$2,500
|
|---|---|---|---|
| Delivery Time | 5 days | 10 days | 30 days |
Number of Revisions | 2 | 2 | 3 |
Bug Investigation | |||
Fix Documentation | - | ||
Detailed Code Comments | - | - | - |
Optional add-ons
You can add these on the next page.
Fast Delivery
+$150 - $1,000Frequently asked questions
74 reviews
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HS
Hans S.
Jul 14, 2026
TFS Wireframe HTML page
Very good work. All in time. Good communication
BT
Blake T.
Jul 7, 2026
Login/Sign Up Page Redesign - Next.js / TailwindCSS UI Web Developer
Oleg is a very good collaborator and fast worker, thank you.
AS
Aliaksei S.
Jul 2, 2026
Auctions Front-End
Oleg was a pleasure to work with. He is dependable, communicates clearly, and pays attention to detail. The project was completed on time and exactly as expected. I highly recommend Oleg to anyone looking for a reliable freelancer.
AS
Aliaksei S.
Jul 2, 2026
Vybar.org
Working with Oleg was a great experience. He is reliable, communicates clearly, and responds quickly. The work was completed on time and met all expectations. I would definitely recommend Oleg and would be happy to work with him again.
AS
Aliaksei S.
Jul 2, 2026
Front End ShikAuto
Oleg is a reliable professional with excellent communication skills. He delivered everything as promised and was easy to work with throughout the project. I highly recommend him!
About Oleg
React Developer | Next.js Developer | Front-End Developer
100%
Job Success
Kharkiv, Ukraine - 1:40 am local time
I often join products that are already in development. You may need to add a new feature, turn a Figma flow into working UI, integrate an API, or improve a frontend that has become difficult to change. I can step into the existing codebase, understand how it works, and move the product forward without unnecessary rewrites.
I have 10+ years of web development experience and 8+ years focused on React. My work covers frontend architecture, state and data flow, API integration, complex forms, performance, loading and error states, and the edge cases that appear once a product has real users.
I can help you:
* add new React or Next.js features to an existing application
* turn Figma designs and product requirements into production-ready UI
* connect complex frontend workflows to REST APIs, GraphQL, and backend services
* build forms, tables, filters, permissions, and data-heavy interfaces
* work with an existing codebase while keeping current user flows stable
* improve frontend code that has become slow or difficult to maintain
* refactor large components, duplicated state, and unclear data flow
* clean up AI-generated or rapidly built React code
* build a new frontend with a structure that can grow with the product
I pay attention to how each change fits into the rest of the application. Clear component boundaries, predictable data flow, reliable state management, and proper loading and error handling help reduce regressions and make future development easier.
I work on SaaS products, customer portals, internal tools, dashboards, onboarding flows, and other production web applications with real business logic. These projects often include complex forms, async data, API integrations, real-time updates, and multiple user states.
Most of my production experience is frontend, but I can also handle the backend side of integration when a feature requires it. I have practical experience with Node.js and NestJS, as well as Supabase and Prisma, so I can work across the API boundary instead of treating the frontend as an isolated part of the product.
Recent results include:
* improved Lighthouse performance from 30 to 96 on mobile and from 40 to 99 on desktop
* stabilized an AI-generated React codebase
* refactored large components and removed duplicated state
* built and extended production features for React, Next.js, SaaS, and data-heavy applications
Core stack:
React, Next.js (App Router, Pages Router), TypeScript, JavaScript
TanStack Query, Zustand, Redux
Tailwind CSS, shadcn/ui, Vanilla Extract
React Hook Form, Zod
REST APIs, GraphQL, Supabase, Prisma, Drizzle
Node.js, NestJS
Vite, React Router, TanStack Router
I can join when you already have a working product, a Figma design, a technical specification, or an early product that needs a stronger frontend foundation.
Tell me what is already built, what needs to ship next, and where the current frontend is slowing you down. I will identify the main technical risks and suggest a practical way to move the work forward.
Steps for completing your project
After purchasing the project, send requirements so Oleg can start the project.
Delivery time starts when Oleg receives requirements from you.
Oleg works on your project following the steps below.
Revisions may occur after the delivery date.
Code audit
I review the codebase to identify technical debt, architectural issues, performance bottlenecks, and unstable patterns.
Refactoring plan
I define the refactoring scope and the safest approach for improving the code without disrupting existing functionality.