React Developer Resume Keywords

What You Need to Know

React developers live in a world where component re-renders happen more often than expected. Understanding useState seems simple until you encounter stale closures where your function references old state values. useEffect appears straightforward until you create infinite loops by forgetting dependencies or including too many. Component performance matters—unnecessary re-renders accumulate, especially in lists with hundreds of items. State management grows complex quickly. Prop drilling through five component levels becomes unmaintainable, leading to Context API or external solutions like Redux. Understanding when to lift state up versus keeping it local affects component reusability. The virtual DOM efficiently updates the real DOM, but large lists still need virtualization with libraries like react-window to maintain performance. React Server Components promise better performance but require rethinking application architecture completely. React has dominated frontend development for years, but mastery requires understanding concepts beyond just writing components. The virtual DOM reconciliation algorithm determines which DOM elements need updating. Component composition patterns affect reusability and maintainability. Unidirectional data flow shapes how data moves through applications. Hooks revolutionized React by replacing class components, but they introduced new patterns and potential pitfalls that take time to master. The useState hook manages component state, but using it correctly isn't always obvious. State updates are asynchronous and batched for performance, meaning you can't read updated state immediately after setState. Functional updates help when new state depends on previous state, preventing bugs from stale closures. Deciding whether state should be local to a component versus lifted to a parent affects component reusability and testing. Too much local state makes components hard to extract and reuse. Too much global state creates unnecessary coupling between components. The useEffect hook replaces lifecycle methods but is more powerful and more confusing. The dependency array is critical—missing dependencies cause stale closures where effects use outdated values, while including too many dependencies causes effects to run too often. Cleanup functions returned from effects prevent memory leaks from subscriptions and timers, but they're easy to forget. The infinite re-render loop occurs when an effect updates state that triggers the effect again. Empty dependency arrays mean effects run only once after initial render, but eslint-plugin-react-hooks warns about missing dependencies for good reasons. Component re-rendering is where React performance problems appear. Every state change causes the component and its children to re-render. For small applications with few components, this doesn't matter. Larger applications need optimization strategies. React.memo prevents component re-renders when props haven't changed, using shallow comparison by default. useMemo memoizes computed values, recalculating only when dependencies change. useCallback memoizes functions, preventing child component re-renders caused by function recreation. But overusing these hooks makes code harder to read without providing significant benefits. Profiling with React DevTools Profiler shows which components re-render and why, guiding optimization efforts. State management at scale requires choosing the right approach for your application. Context API works for simple cases—theme preferences, authentication status, language selection. But Context has limitations. Every consumer re-renders when context value changes, even if they only need part of the data. Splitting contexts helps but adds complexity. Redux provides predictable state management through actions, reducers, and a single store. Redux requires boilerplate—action types, action creators, reducers, middleware. Redux Toolkit reduces boilerplate significantly and has become the recommended approach. Zustand and Jotai provide simpler alternatives with less ceremony but different mental models. Understanding when complexity of state management library is justified versus handling state locally requires experience. Form handling in React is more complex than it initially appears. Controlled components where React owns input state provide full control but require onChange handlers for every input, potentially causing performance issues with large forms. Uncontrolled components using refs reduce boilerplate but provide less control over input values. Form libraries like Formik and react-hook-form reduce boilerplate while providing validation, error handling, and submission logic. React-hook-form uses uncontrolled components internally for better performance. Understanding when form library complexity is justified versus handling forms manually depends on form complexity. Routing with React Router has become standard but requires understanding nested routes, dynamic route parameters, programmatic navigation, and route guards. Client-side routing means servers need configuration to return the React app for all routes, requiring rewrite rules or similar server configuration. Code splitting with React.lazy and Suspense improves initial load time by loading components only when needed. But code splitting adds complexity around deciding split points, handling loading states, and dealing with dynamic imports. Next.js simplifies React development by providing server-side rendering, file-based routing, API routes, and automatic code splitting out of the box. Server-side rendering improves initial page load and SEO. Static site generation provides excellent performance for content that doesn't change frequently. Understanding differences between SSR, SSG, ISR, and CSR helps choose the right rendering strategy.