React Technical Debt Cleanup

Untangling Component Sprawl, State Spaghetti, and Class Lifecycle Tangles

The most common React debt: class components with componentDidMount, componentDidUpdate, and complex lifecycle logic that nobody wants to touch. These components work, but they’re hard to refactor, harder to test, and impossible to extract logic from without converting to hooks first.

State management is usually the second problem. An app that started with Context API for everything now has performance issues because every state change re-renders entire subtrees. Or Redux was introduced for all state - including local UI state that doesn’t belong in a global store - and now every feature requires three files of boilerplate.

Converting Classes to Hooks and Rationalizing Global vs. Local State

We convert class components to functional components with hooks, one component at a time. This isn’t a mechanical transformation - we extract reusable logic into custom hooks, simplify state management, and clean up side effects that were scattered across lifecycle methods.

State management gets rationalized. Server state moves to TanStack Query, which handles caching, refetching, and loading states automatically. Global client state moves to Zustand or stays in Context if it’s truly app-wide. Local state stays local. The result: less code, better performance, clearer data flow.

Scoped Re-Renders, Reusable Custom Hooks, and No More Prop Drilling

Your components become smaller and more focused. Business logic that was buried in componentDidUpdate methods lives in custom hooks that are reusable and testable. Prop drilling disappears because state lives closer to where it’s used.

Performance improves because re-renders are scoped. Instead of a Context change re-rendering 50 components, Zustand selectors ensure only the components that use the changed data re-render. TanStack Query eliminates loading spinners on data that was already fetched. Users feel the difference.

TypeScript Strict Mode, Testing Library Patterns, and Lint Rules That Enforce Architecture

We add TypeScript if it’s missing. Not gradually - we convert the entire project and enforce strict mode in CI. The upfront investment pays for itself within weeks as developers catch type errors before they become bugs.

ESLint rules for hooks, accessibility, and import structure prevent common mistakes. Prettier handles formatting so code reviews focus on logic, not style. We set up React Testing Library to replace Enzyme tests that tested implementation details instead of user behavior. The testing patterns we establish actually catch bugs.

Migrating from Webpack to Vite and Shrinking the Production Bundle

Legacy React projects often carry Webpack configurations that are hundreds of lines long, poorly understood, and painfully slow. We migrate to Vite, which provides instant dev server startup through native ES module serving and significantly faster production builds. Code splitting is configured at the route level using React.lazy and Suspense, so users download only the JavaScript they need for the current page. We audit bundle composition with tools like vite-bundle-visualizer to identify oversized dependencies: a full Moment.js import when date-fns covers the same use case at a fraction of the size, or Lodash imported wholesale when three individual function imports would suffice. Tree shaking is verified to confirm that unused exports are actually eliminated from the production bundle. The outcome is a faster development loop for your team and noticeably shorter load times for your users.