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AI 资讯

Privacy First: Run Your Own Health Assistant LLM Entirely in the Browser (No Backend Required!)

Have you ever wondered why your most personal health queries need to travel across the globe to a centralized server just to get a simple answer? In an era where privacy-preserving AI is becoming a necessity rather than a luxury, the paradigm of Edge AI is shifting the landscape. By leveraging WebLLM and the raw power of WebGPU , we can now execute high-performance Large Language Models (LLMs) directly within the browser sandbox. No API keys, no server costs, and most importantly—zero data leakage. Today, we are building a private health consultation bot that runs 100% client-side. Why Browser-Native LLMs? 🥑 Before we dive into the code, let’s talk about why this matters. Traditional AI architectures rely on heavy GPU clusters. However, with the advent of the WebGPU API, we can tap into the user's local hardware. This approach offers: Ultimate Privacy : Data never leaves the browser. Cost Efficiency : $0 server bills for inference. Offline Capability : Once the weights are cached, you're good to go. If you are interested in more production-ready examples and advanced architectural patterns for decentralized AI, I highly recommend checking out the deep dives over at WellAlly Tech Blog . The Architecture: From Weights to Wasm To make this work, we use TVM (Apache TVM) as the compilation stack, which allows models to run on different backends, and WebLLM as the high-level interface for the browser. Data Flow Diagram graph TD A[User Input] --> B[React Frontend] B --> C[WebLLM Worker] C --> D{WebGPU Support?} D -- Yes --> E[TVM.js Runtime] D -- No --> F[Fallback/Error] E --> G[IndexedDB Model Cache] G --> H[Local GPU Inference] H --> I[Streamed Response] I --> B Prerequisites 🛠️ To follow this tutorial, ensure you have: A browser with WebGPU support (Chrome 113+, Edge, or Arc). Node.js and npm/pnpm installed. The tech_stack : React , WebLLM , TVM , and Vite . Step 1: Setting Up the WebLLM Engine First, we need to initialize the MLCEngine . Since LLMs are heavy, we should

2026-07-12 原文 →
AI 资讯

React Compiler in 2026: What It Actually Memoizes (And What It Doesn't)

Headline: React Compiler — formerly React Forget — shipped stable with React 19 and automatically memoizes components, hooks, and callbacks by analyzing data flow at build time. No dependency arrays to write; the compiler infers them. Here is what it handles, when it opts out, and whether you should delete your useMemo calls. Key takeaways React Compiler inserts useMemo , useCallback , and React.memo automatically at build time — no dependency arrays to maintain. Enable it in Next.js 15/16 with experimental.reactCompiler: true in next.config.ts . The compiler is conservative: if it cannot prove memoization is safe, it emits the component unchanged. "use no memo" is the escape hatch for functions the compiler should not touch. Run npx react-compiler-healthcheck@latest before enabling to see coverage and violations. What does React Compiler actually do? React Compiler transforms component and hook code at build time to insert memoization automatically. Instead of useMemo(() => expensiveCalc(a, b), [a, b]) , the compiler analyzes data flow, determines which values are stable across renders, and emits equivalent memoized code. The compiled output uses React's memo infrastructure at runtime. The compiler is babel-plugin-react-compiler — it works with any Babel-based build pipeline. How do I enable it in Next.js? // next.config.ts const nextConfig = { experimental : { reactCompiler : true , }, }; export default nextConfig ; Before enabling, run the healthcheck: npx react-compiler-healthcheck@latest The healthcheck reports optimizable component count, files with violations, and blocking patterns. Fix violations first for more coverage on day one. What does the compiler memoize? Components — equivalent to React.memo ; re-renders only when props change. Values — equivalent to useMemo ; computed results, derived arrays, objects. Callbacks — equivalent to useCallback : event handlers, functions passed as props. Dependencies are inferred from escape analysis — n

2026-07-12 原文 →
AI 资讯

Partial Prerendering in Next.js: The Static Shell + Dynamic Stream Model

Headline: Partial Prerendering (PPR) in Next.js serves a static HTML shell from the CDN edge instantly, then streams Suspense-wrapped dynamic children from the origin in the same HTTP response. No full-page ISR staleness, no full-page origin latency. I shipped it on two production routes — here is the model. Key takeaways PPR serves a static HTML shell from the CDN edge , then streams dynamic Suspense children from the origin in the same response. The static shell is built at build time — outside <Suspense> renders statically; inside renders dynamically per request. PPR replaces the ISR vs. dynamic tradeoff for pages that are mostly static with isolated personalized sections. No changes to Server Components or Suspense — just experimental.ppr: 'incremental' in config and export const experimental_ppr = true per route. PPR and use cache are complementary : CDN delivery for the shell, origin memoization for dynamic islands. What does PPR actually do? PPR splits a page into two rendering phases within the same HTTP response. At build time, Next.js freezes everything that does not read dynamic request data into a static HTML shell on the CDN edge. At request time, the CDN delivers the shell at edge latency while the origin streams each <Suspense> boundary's content into the same response. On a product page: navigation, title, and description arrive at CDN speed. The in-stock badge and personalized recommendations stream from the origin a fraction of a second later. The user sees a nearly-complete page immediately. How is PPR different from ISR and streaming Suspense? Strategy First byte Dynamic freshness Staleness ISR (revalidate: N) CDN edge Whole page up to N seconds stale Full page Dynamic rendering Origin 100% fresh; waits for slowest query None Streaming Suspense (no PPR) Origin Fresh; TTFB includes origin latency None PPR CDN edge Dynamic islands 100% fresh Static shell only How do I enable PPR? // next.config.ts export default { experimental : { ppr : ' inc

2026-07-12 原文 →
AI 资讯

How I Kept a Live Chat Feed Smooth at 3,700+ Messages

I built LiveShop , a mini live-shopping stream UI, to answer a question I kept running into as a frontend-curious grad: tutorials teach you how to render a list, but they never teach you what happens when that list gets hit with the kind of traffic a real live stream produces. So I built something that would force the problem to show up, then fixed it, then measured whether the fix actually worked. The setup LiveShop simulates a live-shopping broadcast - the kind of interface a small merchant might use to sell products while streaming. A mock event engine fires chat messages, reactions, and purchase notifications on an interval, standing in for what a real WebSocket connection to a streaming backend would deliver. On top of that sits a chat feed, a scrollable product carousel, and a floating reaction animation layer. None of that is unusual. The interesting part started once I asked: what happens when message volume spikes? Where it breaks A naive chat feed is just messages.map(m => <ChatRow key={m.id} {...m} />) . It's the first thing anyone reaches for, and it's fine — right up until it isn't. At 50 messages, nothing looks wrong. At a few hundred, every new message triggers a full re-render pass across every row in the DOM, including the hundreds that have already scrolled out of view and that nobody can see. The browser is doing layout and paint work for pixels that aren't on screen. In a real live stream, this is exactly the wrong failure mode, because message volume doesn't arrive evenly. It spikes — right after a product drop, right when something funny happens on stream, right when a popular creator says something quotable. That's precisely the moment a chat feed can't afford to stutter, and precisely the moment a naive implementation is most likely to. What I measured Rather than guess whether this mattered, I built a way to test it directly. LiveShop has a "Simulate spike" button that fires 500 messages instantly, plus a live FPS readout using requestAnimat

2026-07-11 原文 →
AI 资讯

Day 128 of Learning MERN Stack

Hello Dev Community! 👋 It is officially Day 128 of my software engineering marathon! Today, I tackled an essential lifecycle design challenge in modern frontend development: managing persistent browser loops, orchestrating ticking background workers, and mastering Timer Cleanups inside the useEffect Hook ! ⚛️⏱️💻 I put these architectural paradigms into action by engineering a lightweight, responsive Real-Time Clock Application that tracks exact server-client time down to the second without triggering rogue background processor spikes! 🛠️ Deconstructing the Day 128 Asynchronous Scheduler As captured across my clean system workspace configurations in "Screenshot (286).png" and "Screenshot (287).png" , the scheduling mechanism enforces strict resource allocation: 1. Initializing Reactive Temporal State Managed our standard state anchor using native JavaScript runtime Date models to trigger instant re-renders upon completion of each interval cycle: javascript const [time, setTime] = useState(new Date());useEffect(() => { let intervalId = setInterval(() => { setTime(new Date()); }, 1000);

2026-07-10 原文 →
AI 资讯

Day 127 of Learning MERN Stack

Hello Dev Community! 👋 It is officially Day 127 of my software engineering marathon! Today, I leveled up my asynchronous data pipeline in React.js by tackling a critical production-grade performance problem: avoiding memory leaks and managing component unmounting states using the useEffect Cleanup function alongside the native browser AbortController API ! ⚛️🛡️⚡ Additionally, I integrated a fully responsive async loading engine to drastically improve our overall User Experience (UX). 🛠️ Deconstructing the Day 127 Network Boundary Control As shown inside my refactored workspace code layout across "Screenshot (283)_2.png" and "Screenshot (284)_2.png" , the side-effect layer is now safe from ghost background executions: 1. Ingesting the Abort Signal API Inside the lifecycle layer, before initiating the endpoint call, I instantiated an active execution cancellation anchor on Lines 12-13 inside PostContainer.jsx : javascript const controller = new AbortController(); const signal = controller.signal;

2026-07-10 原文 →
AI 资讯

Day 125 of Learning MERN Stack

Hello Dev Community! 👋 It is officially Day 125 of my software engineering marathon! Today, I crossed an elite milestone in frontend data architecture: moving completely away from local hardcoded mock lists by connecting my centralized state management infrastructure to live third-party servers using the Fetch API alongside Async/Await ! ⚛️🌐⚡ Now, the social media feed dynamically handles server-side data models, passes payloads to an active state reducer, and broadcasts states down to presentation layers via a custom Context portal! 🛠️ Deconstructing the Day 125 Async Network Lifecycle As shown inside my development setup across "Screenshot (279).png" , "Screenshot (280).png" , and "Screenshot (281).png" , the application state engine is clean and modular: 1. Extensible Central State Reducers ( PostList.jsx ) Engineered explicit structural actions inside the reducer core to seamlessly support both user generation and full-scale network array overriding: javascript } else if (action.type === "NEW_INITIAL_POSTS") { NewPostValue = action.payload.posts; }

2026-07-10 原文 →
AI 资讯

Our Journey to GSSoC 2026: Omnikon's Repository Has Been Selected! 🎉

Open source has always been at the heart of what we do at Omnikon. Today, we're excited to share a milestone that means a lot to our entire community. Our repository, maintained by Sourabh, has been officially selected for GirlScript Summer of Code (GSSoC) 2026. For us, this isn't just another achievement—it's a step toward building a stronger open-source ecosystem where students and developers can learn, collaborate, and create meaningful software together. About Omnikon Omnikon is a student-led open-source organization focused on building high-quality developer tools, educational resources, and community-driven projects. Our mission is simple: Build impactful open-source software. Help new contributors get started. Create projects that solve real problems. Foster a welcoming developer community. Every repository we build is designed with collaboration in mind, making it easier for contributors of all experience levels to participate. What GSSoC Means GirlScript Summer of Code is one of India's largest open-source programs. Every year, thousands of contributors participate by solving issues, improving documentation, fixing bugs, and implementing new features across selected repositories. Being selected means our project will become part of this collaborative ecosystem, giving contributors an opportunity to make meaningful contributions while learning industry-standard development workflows. A Special Thanks This achievement wouldn't have been possible without Sourabh, who maintained and prepared the repository throughout the selection process. A huge thank you to everyone who contributed ideas, reviewed code, reported issues, improved documentation, and supported the project. Open source is never the work of one person—it grows because of a community. What's Next? We're preparing the repository for contributors by: Organizing beginner-friendly issues. Improving documentation. Creating contribution guides. Enhancing project structure. Mentoring new contributors thro

2026-07-10 原文 →
AI 资讯

WCAG 2.2 Accessibility for React Developers — Practical Guide

I'm Safdar Ali , a frontend engineer in Bengaluru. Last quarter I audited a client dashboard that looked polished — clean Tailwind, smooth transitions, Lighthouse performance in the 90s — and failed basic keyboard navigation in under two minutes. Tab order jumped randomly, modals trapped nothing, and icon-only buttons had no labels. WCAG 2.2 is not a legal checkbox for enterprise contracts alone. It is how you ship React UI that works for everyone: screen reader users, keyboard-only users, people on slow 4G with zoom enabled, and your future self debugging at 11pm. This guide covers the wcag 2.2 react patterns I run before every merge. Why WCAG 2.2 matters for React in 2026 WCAG 2.2 added criteria that directly affect React apps: focus not obscured, dragging movements, target size minimums, and consistent help. React's component model makes accessibility both easier and easier to break — you can encapsulate good patterns in a shared Dialog component, but you can also copy-paste a div-with-onClick button across forty files. The legal landscape in India is catching up. Government portals and fintech products increasingly require accessibility audits before launch. Even when nobody asks, inclusive UI reduces support tickets — unclear error messages and broken focus management generate more "the form is broken" emails than actual backend failures. React does not ship accessible components by default. A is focusable; a is not, unless you wire it. Your job is to make the accessible path the default path in your design system. Focus traps — modals that actually work A focus trap keeps keyboard focus inside a modal until the user dismisses it. Without one, Tab sends focus to elements behind the overlay — confusing for sighted keyboard users and disorienting for screen reader users who hear content from two layers at once. Continue Reading...

2026-07-10 原文 →
开发者

History of JavaScript: Browser wars, ECMAScript, Node.js, TypeScript, and React

It only took ten days to develop the language that powers the web. This article tells the story of JavaScript and the tools that helped shape it. 1995. The birth of a legend The idea for JavaScript was born at Netscape. At the time, web pages consisted almost entirely of HTML, and Netscape wanted to make them more interactive. The first step in that direction was licensing Java for use in the Netscape browser. However, Java's complexity proved challenging for web designers. Brendan Eich was then tasked with creating a programming language that wasn't too complex and could be embedded directly into HTML pages. Eventually, Marc Andreessen, co-founder of Netscape Communications, and Bill Joy, co-founder of Sun Microsystems, also contributed to the language development. To meet the deadline for the Netscape browser release, the companies agreed to collaborate on the language. During its development, the language changed its name several times. For example, the first version Eich created in just ten days was called Mocha. It was then renamed to LiveScript. The final name was chosen because the word Java was already popular and well-known. JavaScript was first announced shortly before the second beta release of Netscape Navigator. Meanwhile, Netscape announced that 28 leading IT companies planned to incorporate JavaScript into their future products. JavaScript 1.0 was released in 1996 alongside Netscape Navigator 2. 1997-1999. ECMAScript In 1996, Microsoft also released JScript as part of Internet Explorer 3, which was an open-source implementation of JavaScript for Windows. By the way, the name was changed to avoid negotiating trademark rights for Java with Sun Microsystems. To eliminate browser incompatibilities caused by different implementations, Netscape handed the JavaScript specification over to the ECMA international organization. So, the ECMA-262 specification was created. The language got the name ECMAScript because JavaScript was already trademarked. Around the

2026-07-09 原文 →
AI 资讯

Article: Beat-Aligned Mobile Audio Streaming with Virtual Chunks and Native Playback

In this article, I describe the challenges and the design of a React Native real-time mobile beat-aligned playback system for iOS and Android. The system combines personalization with low-latency, and seamless navigation and was the result of careful analysis and experimentation to address strict mobile and network constraints as well as meet user expectations. By Vladyslav Melnychenko

2026-07-09 原文 →
AI 资讯

littlebag Creator Seeks User Feedback to Validate 343-Byte UI Framework's Utility Despite Performance Limitations

Introduction: Unveiling littlebag Meet littlebag , a reactive UI framework that defies conventional expectations by packing essential features into a mere 343 bytes (minified and brotlified). This isn’t just a technical curiosity—it’s a proof of concept that challenges the notion that UI frameworks must be bloated to be functional. littlebag includes: Reactive state management via state and effect , enabling dynamic updates without manual DOM manipulation. An html element factory that inherently supports reactivity, reducing boilerplate code. Conditional rendering with keyed , allowing efficient updates to specific UI segments. Reactive lists using each , simplifying the handling of dynamic data collections. TypeScript declarations , ensuring type safety and developer productivity. The framework’s size is achieved through aggressive tree-shaking and code minimization , stripping away all non-essential logic. However, this comes at a cost: performance limitations due to the absence of optimizations like virtual DOM diffing or batch updates . Each reactive update triggers direct DOM manipulation, which can lead to layout thrashing —a mechanical process where frequent reflows and repaints cause frame rate drops, making the UI feel sluggish. Inspired by VanJS (1 kB) and its dependency on an additional 1.2 kB library (Van X), littlebag aims to eliminate such overhead. Yet, its current state is experimental. Without user feedback, it risks remaining a niche project, failing to address its performance bottlenecks or evolve into a viable alternative to larger frameworks. The creator’s plan to add Server-Side Rendering (SSR) hinges on community interest, but SSR itself introduces complexity—requiring a custom DOM implementation to avoid client-side hydration costs. If users engage, littlebag could become a lightweight SSR solution; if not, it may stagnate as a curiosity. The stakes are clear: littlebag’s utility depends on whether it can balance its minimalism with practical

2026-07-09 原文 →
AI 资讯

The Complete Redbelly EligibilitySDK Integration Guide: Widget to Backend to On-Chain

The Redbelly Network EligibilitySDK is the compliance backbone for any dApp that needs to verify user eligibility (KYC, KYB, investor accreditation) before letting a wallet in. The official documentation covers each piece well on its own reference page, but there is no single walkthrough connecting the frontend widget to the backend verifier to the on-chain permission check to a production deployment. This guide is that walkthrough. Everything here was verified against the live documentation at https://docs.redbelly.network/ in July 2026: contract addresses, route names, config fields, issuer DIDs and every error string in the reference section. Every code example was then compiled against the published SDK package (v0.0.31) on React 19 with Vite and on Next.js 16 with the App Router, and the backend verifier was booted and exercised for real. Where the docs and reality diverge (a quickstart repo that is not publicly visible, a credential faucet still under development, three undocumented behaviours the builds surfaced), the guide says so and gives you the workaround. What you will build, in order: A mental model of the two verification mechanisms (and why conflating them costs you a day) A working backend verifier with the three routes the widget demands A plain React integration with full loading and error states A production-grade Next.js App Router setup: secure proxy, SIWE sessions, request gating, and both static and dynamic rendering approaches An end-to-end test run on Redbelly Testnet The decision logic for choosing between the three SDK flows, and the pattern for combining them A complete error reference: every documented error, its cause, and its fix A developer following this guide should have the widget running inside an existing dApp within about four hours. 1. Overview and Architecture What the EligibilitySDK actually is The Redbelly "Onboarding and Eligibility Kit" ( @redbellynetwork/eligibility-sdk ) is a set of React components and hooks for provin

2026-07-09 原文 →
AI 资讯

DEMYSTIFYING REACT COMPONENT INSTANCES

Hello fellow React developers! In this article we will be breaking down what React component instance is and scenarios where React component instance is at play. What is a React Component ? Before we can understand and really appreciate what a React component instance is, we first need to understand what a component itself is. Basically, components are the fundamental building blocks of any React application. They are independent, reusable pieces of code that allow you to split your application into distinct, manageable bits of logic and UI. From our knowledge of JavaScript, you can think of components in a way as what a function is. Just as we create and use functions to avoid repeating code and separate logic, components are used to divide our application into reusable visual chunks. However, they work in isolation and return HTML (via JSX) to describe what appears on the UI. Let take a look at a simple Greetings component used in a demo; Instead of writing the HTML layout for a greeting over and over again, we define it once as a component and reuse it multiple times in our application by passing different props (arguments). React Component Instances: What are they ? Now that we understand what a React component is, let's move on to React component instances. In programming, an instance is a concrete object created from a specific template (such as a JavaScript class or a Constructor function). In React, a component instance is the actual implementation of a component in a React application. It is a long-lived object that holds contextual information about a particular component. Every time a component is rendered in our application, React creates a new instance of that component. To help you visualize this, let’s take a look at a simple Counter component; // A Counter Component import React , { useState } from ' react ' ; export default function Counter () { const [ count , setCount ] = useState ( 0 ); return < button onClick = {() => setCount ( count + 1 )} > C

2026-07-08 原文 →
开发者

React Doctor marcó 1,249 problemas en una SPA de React. Cinco valían la pena arreglar

React Doctor es un linter de cero instalación que escanea un codebase de React buscando problemas de correctitud, seguridad, accesibilidad, rendimiento y mantenibilidad, luego los rankea y te entrega una lista de arreglos con forma de agente. Este post es un reporte de campo: lo corrí sobre una SPA real de React 18 + Vite + TypeScript (~50 rutas, TanStack Query, react-hook-form) y separé lo que de verdad me atrapó. El resultado honesto: 1,249 hallazgos, cinco que valía la pena arreglar, incluyendo dos bugs de seguridad reales. Los otros 1,244 fueron una mezcla de ruido, decisiones de criterio, y falsos positivos. TL;DR Categoría Reportados Vale la pena actuar Por qué la brecha Seguridad 18 warnings 2 13 eran sinks saneados en el servidor (falsos positivos); 1 mina de código muerto + 1 XSS real fueron el oro Bugs 24 errores, 487 warnings 2 1 fuga de timer, 1 key/spread; ~27 exhaustive-deps piden criterio humano Accesibilidad 434 warnings, 1 error 1 el 1 error ( aria-selected faltante) era real; los 434 son ruido de <Label> / <button type> Rendimiento 110 warnings 0 nada caliente; candidatos pero sin impacto medido Mantenibilidad 176 warnings 0 opiniones de estilo tipo "componente grande" Total 1,249 5 señal-a-ruido ≈ 1 en 250 El puntaje que imprimió: 39 / 100 . Dos cosas que ese encuadre esconde: los cinco que sacó a la superficie eran de alto valor (una fuga de token en localStorage y un sink de XSS almacenado), y el conteo no es determinista : una segunda corrida del mismo commit reportó 1,254, no 1,249. El veredicto en una línea: excelente generador de hipótesis, pésima compuerta. Úsalo para encontrar candidatos, verifica cada uno contra el código, y nunca conectes el conteo al CI. Qué es React Doctor Un solo binario que corres por npx / pnpm dlx , sin agregar dependencia a tu proyecto, sin archivo de configuración obligatorio. Parsea tu src/ , hace match contra un conjunto de reglas (sus familias: Seguridad, Bugs, Accesibilidad, Rendimiento, Mantenibilidad), e im

2026-07-08 原文 →
AI 资讯

TanStack Start vs Nuxt: One Framework to rule them all?

I love Nuxt and I really like TanStack Start. But which one is better? Or are they about the same? And if they are about the same, does it do anything my Nuxt setup can't, and is that worth leaving Vue for React? So I decided to build the same app in both frameworks and take a look. Read on below to find out! If you'd rather watch a video, check out the video on the same topic! The app In both frameworks I built a small GitHub user lookup app. You type a username, the profile gets fetched on the server, and the username lands in the URL as a ?user= query param so the result is shareable. Type ErikCH , hit enter, and the card renders. Refresh the page and it's still there. It has the same behaviour so the difference lies in the code. Difference one: server functions vs server routes On the Nuxt side we call a server route from useAsyncData . Server are the more idiomatic way to use Nuxt to call things on the server. <!-- app/pages/index.vue --> < script setup lang= "ts" > import { z } from ' zod ' import type { GithubUser } from ' ~~/server/api/github.get ' definePageMeta ({ props : route => z . object ({ user : z . string (). default ( '' ) }). parse ( route . query ), }) const props = defineProps < { user : string } > () const router = useRouter () const input = ref ( props . user ) const { data , error } = await useAsyncData ( ' github-user ' , () => props . user ? $fetch < GithubUser > ( ' /api/github ' , { query : { user : props . user } }) : Promise . resolve ( null ), { watch : [() => props . user ] }, ) function lookup () { router . push ({ query : { user : input . value . trim () } }) } </ script > The props option on definePageMeta maps the query into a typed page prop and re-runs on client navigation. useAsyncData fetches when there's a username and refetches whenever it changes. The conditional that returns Promise.resolve(null) skips the request on an empty query param, (or when you first load). The server route does the outbound call: // server/api/gith

2026-07-08 原文 →
AI 资讯

AbortController: The Async Cleanup Pattern You Keep Skipping

Most async code in frontend apps has a hidden bug: it doesn't stop when it should. A user navigates away mid-request. A component unmounts. A newer search query supersedes the previous one. The old network call keeps running, eventually resolves, and tries to update state that no longer exists. In React, that's the infamous warning: "Can't perform a React state update on an unmounted component." In vanilla JS, it silently delivers stale data. AbortController is the browser's built-in solution. It's been in every major browser since 2018 — old enough that there's no excuse not to use it. But most tutorials skip it, most codebases use it inconsistently, and most devs reach for it only after they've debugged a flicker one too many times. Here's the pattern, end to end. The race condition you already have function SearchResults ({ query }: { query : string }) { const [ results , setResults ] = useState < Result [] > ([]); useEffect (() => { fetch ( `/api/search?q= ${ query } ` ) . then ( r => r . json ()) . then ( data => setResults ( data )); // runs even if query changed }, [ query ]); return < ul > { results . map ( r => < li key = { r . id } > { r . name } </ li >) } </ ul >; } When the user types "re" and then "rea" before the first request finishes, two fetches are in flight simultaneously. The request for "re" might complete after the request for "rea" — and when it does, setResults silently overwrites the correct result with the stale one. The component shows the wrong data. No error, no warning, no clue. This is a race condition, not a hypothetical. It happens on slow networks, during fast typing, on underpowered devices, and in staging environments right before a demo. AbortController: the three-line fix An AbortController is a pair: a controller object and a signal. You pass the signal into any abort-aware API; you call abort() to cancel it. useEffect (() => { const controller = new AbortController (); fetch ( `/api/search?q= ${ query } ` , { signal : control

2026-07-07 原文 →
AI 资讯

Why I stopped using online image compressors and built a CLI instead

Four years of optimizing React and Next.js projects taught me one thing: unoptimized images are everywhere, and nobody wants to fix them. Every project has the same pattern. Heavy PNG and JPG files are sitting inside /public , there is no consistent image pipeline, and some of those files have no business being that large in a production codebase. This is especially common in small and mid-sized projects. There is no CDN transformation layer or dedicated asset pipeline. Images get added while the product is moving quickly, and the cleanup becomes a task for “later.” Later, of course, never comes. Then, at 1am, while refactoring an extremely vibe-coded Next.js project, I found myself doing the cleanup manually again. Find an image. Upload it to an online compressor. Hit the free limit. Open another tool. Convert a few more. Download everything. Replace the original files. Hunt through the codebase for every import and src path. Hope I did not miss one. And I finally thought: I am a developer. Why am I doing this by hand? So I built pixcrush . npx pixcrush . One command to convert the images, compress them, and update their matching code references automatically. “But doesn’t Next.js already optimize images?” Yes, and if your application uses next/image consistently, you should absolutely take advantage of it. The Next.js <Image> component can resize images for different devices, lazy-load them, and serve modern formats such as WebP. Files inside /public can be referenced from the root URL, while statically imported images also give Next.js access to their intrinsic dimensions. The official Next.js image documentation explains these runtime optimizations in detail. But that solves a different layer of the problem. I wanted to clean up the source assets themselves: Replace heavy PNG and JPG files with smaller WebP files when conversion is worthwhile. Update existing imports and string-based image paths across the repository. Identify images that are no longer reference

2026-07-07 原文 →