React

This article summarizes the DEV post “How to Use React Query for Efficient Data Fetching” and focuses on a minimal, production-ready setup. Why React Query (TanStack Query) Handles fetching, caching, retries, background refresh, and deduping. Removes useEffect + manual loading/error state boilerplate. Scales to pagination, infinite scroll, and SSR hydration. 3-step setup Install: npm install @tanstack/react-query Create a client and wrap your app: import { QueryClient, QueryClientProvider } from "@tanstack/react-query"; const queryClient = new QueryClient(); const App = () => ( <QueryClientProvider client={queryClient}> <MyComponent /> </QueryClientProvider> ); Fetch with useQuery: import { useQuery } from "@tanstack/react-query"; function UsersList() { const { data, isLoading, error } = useQuery({ queryKey: ["users"], queryFn: () => fetch("/api/users").then((r) => r.json()), }); if (isLoading) return <p>Loading…</p>; if (error) return <p>Something went wrong</p>; return <ul>{data.map((u) => <li key={u.id}>{u.name}</li>)}</ul>; } Features you get “for free” Auto refetch on window focus/network reconnect. Stale-while-revalidate caching with configurable TTLs. Retries with exponential backoff for transient failures. Query invalidation to refresh related data after mutations. Devtools for live inspection of query states. Power tips Prefetch likely-next routes to hide latency (e.g., on hover). Use useInfiniteQuery for endless scroll; surface hasNextPage/fetchNextPage. Pass auth tokens via queryFnContext; centralize fetcher. For SSR/Next.js, hydrate with dehydrate/Hydrate to avoid waterfalls. Performance guardrails Set per-query stale times and retry counts to balance freshness vs. load. Log slow queries and cache hit rate; watch INP/LCP when triggering refetches. Keep query keys stable and descriptive (e.g., ["post", postId]). Bottom line: React Query removes state-management overhead for remote data and delivers faster, more resilient UIs with minimal code.

A critical security vulnerability has been discovered in React’s Server-Side Rendering (SSR) Server Action protocol that could lead to Remote Code Execution (RCE) on the server. The Vulnerability The issue lies in how React handles Server Actions in SSR environments. When improperly configured, the Server Action protocol can allow attackers to execute arbitrary code on the server. How It Works Server Actions in React allow you to call server-side functions directly from client components: ...

This summary distills the DEV post “⚡ Vite vs Turbopack — The Present & Future of Frontend Build Tools (2025 Edition)” into key takeaways for teams choosing a tool. Quick comparison Dev speed: Vite is already blazing (ESM + on-demand transforms). Turbopack pushes incremental builds in Rust—slightly better for very large repos. HMR: Vite is instant/reliable; Turbopack is fast and improving. Ecosystem: Vite is framework-agnostic with a large plugin ecosystem; Turbopack is strongest in Next.js today. Prod builds: Vite uses Rollup; Turbopack still leans on Webpack for prod (transitioning). Future: Vite is experimenting with Rolldown (Rust-based Rollup successor) to close the Rust gap. How Vite works (dev vs prod) Dev: native ESM served directly; deps pre-bundled once with esbuild; code transformed on demand. Prod: Rollup bundles with tree shaking, code splitting, and minification. Turbopack highlights Rust core focused on incremental/parallel builds and heavy caching. Today powers Next.js dev mode; production migration is ongoing. When to choose which Pick Vite for framework-agnostic projects, small–medium apps, or when you want the broadest plugin ecosystem and stable DX. Watch Turbopack for large Next.js/monorepo scenarios that will benefit most from incremental builds as it matures. Tips for Vite performance Use explicit imports; avoid barrel files; warm up frequently used files; keep plugin set lean; prefer native tooling (CSS/esbuild/SWC). Bottom line: In 2025 Vite is the safe, fast default for most teams; Turbopack is promising for big Next.js codebases and will get more interesting as Rust-based production builds land.

This note condenses the DEV article “Mastering Frontend Performance: Harnessing the Power of Caching” into actionable steps for modern apps. Why cache Reduce network and CPU cost for repeated data/computation. Improve perceived speed and resilience to flaky networks. Keep UIs responsive under load. Layers to combine HTTP caching: set Cache-Control, ETag, Last-Modified, stale-while-revalidate for API/static responses; prefer immutable, versioned assets. Client memoization: cache expensive computations/render data (useMemo, useCallback, memoized selectors). Data caching: use React Query/SWR/Apollo to dedupe fetches, retry, refetch on focus. Service worker (when appropriate): offline/near-edge caching for shell + static assets. React hook hygiene Memoize derived data: useMemo(() => heavyCompute(input), [input]). Memoize callbacks passed to children to avoid re-renders: useCallback(fn, deps). Keep props stable; avoid recreating objects/functions each render. HTTP cache playbook Static assets: long max-age + immutable on versioned filenames. APIs: choose strategy per route: idempotent reads: max-age/stale-while-revalidate with ETag. personalized or sensitive data: no-store. list endpoints: shorter max-age + revalidation. Prefer CDN edge caching; compress (Brotli) and serve modern formats (AVIF/WebP). UI checks No spinner longer than a couple of seconds; use skeletons and optimistic updates where safe. Avoid layout shift when cached data arrives—reserve space. Track Core Web Vitals (LCP/INP/CLS) and hit-rate for key caches. Quick checklist Versioned static assets + long-lived caching headers. API cache policy per route with ETag/stale-while-revalidate. React memoization for heavy work and stable callbacks. Data-layer cache (React Query/SWR) with sensible stale times + retries. RUM/CI dashboards watching Web Vitals and cache hit rates. Takeaway: Combine HTTP caching, client memoization, and data-layer caches to ship faster pages and keep them fast under real traffic.

Optimizing React applications is crucial for better user experience. Here are proven techniques. 1. Memoization React.memo const ExpensiveComponent = React.memo(({ data }) => { return <div>{processData(data)}</div>; }, (prevProps, nextProps) => { return prevProps.data.id === nextProps.data.id; }); useMemo const expensiveValue = useMemo(() => { return computeExpensiveValue(a, b); }, [a, b]); useCallback const handleClick = useCallback(() => { doSomething(id); }, [id]); 2. Code Splitting React.lazy const LazyComponent = React.lazy(() => import('./LazyComponent')); function App() { return ( <Suspense fallback={<div>Loading...</div>}> <LazyComponent /> </Suspense> ); } 3. Virtualization import { FixedSizeList } from 'react-window'; function VirtualizedList({ items }) { return ( <FixedSizeList height={600} itemCount={items.length} itemSize={50} > {({ index, style }) => ( <div style={style}>{items[index]}</div> )} </FixedSizeList> ); } 4. Avoid Unnecessary Renders // Bad: Creates new object on every render <ChildComponent config={{ theme: 'dark' }} /> // Good: Use useMemo or constant const config = useMemo(() => ({ theme: 'dark' }), []); <ChildComponent config={config} /> Best Practices Memoize expensive computations Split code by routes Virtualize long lists Avoid inline functions/objects Use production builds Conclusion Optimize React apps for better performance! ⚡

Rust WebAssembly can significantly improve React application performance. Here’s how to integrate it. Setup cargo install wasm-pack wasm-pack build --target web Rust Code use wasm_bindgen::prelude::*; #[wasm_bindgen] pub fn add(a: i32, b: i32) -> i32 { a + b } React Integration import init, { add } from './pkg/rust_wasm.js'; async function loadWasm() { await init(); console.log(add(2, 3)); // 5 } Performance Benefits Faster computation for heavy operations Memory efficient Type safe Near-native performance Best Practices Use for CPU-intensive tasks Minimize data transfer Profile performance Handle errors properly Bundle efficiently Conclusion Boost React performance with Rust WebAssembly! ⚡