React useEffect misuse: Avoid using for rendering, state resets, and parent callbacks

🚀 Mastering Performance: React Memoization & Modern Tooling I've been diving deep into web performance optimization, specifically focusing on how React handles re-renders and the impact of modern build tools like Vite. Here is a breakdown of my recent learnings: * Vite & the Move to OXC While older versions of Vite relied on Rollup for bundling, Vite @latest leverages the OXC compiler. Rollup: Excellent for combining multiple files into a single bundle. OXC: A high-performance compiler toolset that processes individual pieces of code much faster than traditional tools like Babel. * Memoization: Why It Matters Memoization is all about efficiency—remembering work already done so it doesn't have to be repeated. In React, this is crucial for preventing "falty reconciliation" (unnecessary re-renders). The Problem: Since functions are reference data types, their memory address changes on every render of a parent component. This causes child components (like an <About /> component) to re-render even if their data hasn't changed. The Solution: Using React.memo to cache the component. This saves RAM and processing power by ensuring a re-render only happens if the props actually change. - Key Techniques Learned: Component Memoization: Using React.memo() (via Higher Order Component or direct definition) to prevent unnecessary child updates. Function & Value Memoization: Utilizing the useCallback and useMemo hooks for granular control over memory and reference stability. Logic Check: React.memo performs a shallow comparison: $PrevProp === NewProp$ ? No Re-render : Re-render. Staying updated with these optimizations is key to building fast, scalable, and user-friendly applications! #ReactJS #WebDevelopment #FrontendEngineering #Vite #PerformanceOptimization #CodingTips #JavaScript #Memoization

Just dove into the new React Compiler and my entire memoization game is busted. 🤯 Turns out, I was over-optimizing the wrong things, leading to more overhead than actual gains. It's a humbling but incredibly valuable lesson. Here's what the compiler exposed about my old habits:  • 𝗢𝘃𝗲𝗿-𝗿𝗲𝗹𝗶𝗮𝗻𝗰𝗲 𝗼𝗻 `𝘂𝘀𝗲𝗠𝗲𝗺𝗼`: I was wrapping everything, even simple props, just in case. The compiler handles many of these automatically.  • 𝗠𝗲𝗺𝗼𝗶𝘇𝗶𝗻𝗴 𝗱𝗲𝗿𝗶𝘃𝗲𝗱 𝘀𝘁𝗮𝘁𝗲: Complex calculations are still prime candidates, but basic derivations often don't need the extra `useMemo` layer.  • 𝗖𝗼𝗻𝘁𝗲𝘅𝘁 𝗔𝗣𝗜 𝗺𝗶𝘀𝘂𝘀𝗲: Memoizing context values unnecessarily was a performance drain I didn't see coming. The compiler's automatic memoization is smarter than I gave it credit for. It intelligently skips re-renders for stable values, meaning our manual `useMemo` calls were often redundant and even detrimental. It's a paradigm shift. Embrace the compiler; it might just fix your performance issues without you lifting a finger. Save this post if you're also rethinking your memoization strategy. Follow for more real-world tech insights and practical dev tips. #React #JavaScript #WebDevelopment #Frontend

React is unidirectional. Data flows down. If you’ve spent any time in React, you know the drill, parents talk to children via props. It’s predictable, and it’s why the library scales. But it leads to the inevitable question, How does the child talk back? It’s not a "reverse prop" or some hidden magic. It’s actually a classic JavaScript pattern. While data flows down, functions are first-class citizens. To let a child communicate, the parent defines a "handler" function and passes it down as a prop. The child doesn't send data up in the traditional sense, it simply executes the function it was given. This is the essence of lifting state up. The parent keeps the "source of truth," and the child remains reusable, only triggering the parent’s logic when an event occurs. Of course, once you’re passing functions down five levels deep, you’re in prop drilling hell. That’s usually the signal to reach for the Context API or a state manager like Zustand to keep your components clean. Are you - context API purist? - prefer a dedicated state manager for handling these flows? #ReactJS #WebDevelopment #SoftwareEngineering #Frontend #Javascript

The Future of React: Embracing the React Compiler For years, `useMemo` and `useCallback` have been essential tools for optimizing React applications, helping developers manage performance by preventing unnecessary re-renders. However, as we move into 2026, the landscape of React development is undergoing a significant transformation with the increasing adoption and standardization of the React Compiler. This paradigm shift means that manual memoization, once a best practice, is becoming less critical. The React Compiler intelligently optimizes your components at build time, effectively eliminating the need for developers to manually wrap functions and values. This not only leads to cleaner, more readable code but also frees up development time to focus on core logic and user experience. What does this mean for developers? • Simplified Codebase: Say goodbye to the boilerplate of `useMemo` and `useCallback`, resulting in more concise and maintainable components. • Automatic Performance Gains: The compiler handles optimizations automatically, ensuring your applications run efficiently without constant manual intervention. • Enhanced Developer Experience: Focus on writing functional code, knowing that performance concerns are being addressed under the hood. This evolution marks a pivotal moment for the React ecosystem, promising a future where performance optimization is seamlessly integrated into the development workflow. Are you ready to embrace a cleaner, more efficient way of building with React? #ReactJS #WebDevelopment #FrontendDevelopment #ReactCompiler #CodingBestPractices #DeveloperExperience #JavaScript #TechTrends #SoftwareEngineering

I used to write this to get a user's city from an API response: user && user.address && user.address.city Then I discovered two operators that changed everything. 😅 → ?. optional chaining — if it's null, just return undefined. No crash. → ?? nullish coalescing — if it's null or undefined, use this default instead. → ?? is smarter than || — it won't replace 0 or "" with your default. Huge difference. → Combine them: user?.address?.city ?? "Unknown" — safe access + fallback in one line. → Works on functions too — user.getName?.() only calls it if it exists. Once you start using these — you'll wonder how you lived without them. 😄 Were you using && for this before? Drop a comment 👇 #javascript #webdevelopment #frontend #programming #javascripttips #learnjavascript #100daysofcode #reactjs #coding #softwareengineering

I've been working on a research paper on the side. It just went live as a preprint - and I could use some help from people who know this space. Here's what I built and what I found. The React Compiler silently breaks Valtio and MobX. No crash, no warning. Your components just stop updating when they should. Production looks clean. I found this while running a controlled benchmark of 7 React state management libraries across 13 interaction scenarios. The core numbers: → Redux, Zustand, Jotai, Valtio, MobX + React.memo = 0 surplus re-renders when unrelated state changes → React Context = 50 surplus re-renders for the same workload → That gap = 1,632 ms of scenario-level overhead → Scale to 10 consumers = 500 surplus re-renders per burst Replicated on 4 hardware platforms (M5 Max, M3 Max, i9, M1) and 3 JS engines (V8, SpiderMonkey, JavaScriptCore). The benchmark enforces byte-for-byte identical JSX across all 7 builds — the subscription model is the sole independent variable. Reproduces with one command. Why I'm posting this: This is my first research paper. I'm an independent researcher — no institution, no lab, no advisor. I'm looking for: → A faculty co-author who can review the methodology and provide institutional backing for journal submission → Feedback from anyone in the React community or empirical SE space → Leads on appropriate venues for formal submission If this sounds like something you'd want to collaborate on, please reach out. If you use Valtio or MobX with the React Compiler enabled, your components may already be broken. Add "use no memo" to store-consuming components. Paper and code in the comments. cc: Daishi Kato (Zustand, Jotai, Valtio) — Michel Weststrate (MobX) and Mark Erikson (Redux Toolkit), curious what you think too. #React #JavaScript #Frontend #WebPerformance #OpenSource #AcademicResearch

2 posts ago: a 9,200-line React codebase from 2019. Today: migration done. The numbers: 📊 Codebase - 77 files → 142 focused modules - 0% → 100% TypeScript strict - 11 runtime deps → 3 🛡️ Removed entirely - jQuery - moment.js - axios 0.19 (known CVEs) - Redux + react-redux + redux-thunk - create-react-app 3.4 (abandoned) - Console.log interceptors leaking tokens ⚡ Tooling - HMR: ~8s → <1s (CRA → Vite 8) - react-router v5 → v7 - tsc --strict: 0 errors - ESLint flat config: 0 warnings 🕐 Time - Manual rewrite: weeks, team - My pipeline: days, solo Note: LOC actually *went up* (9.2k → 12.4k). That's what a real migration looks like — types, split files, typed API layer. The win isn't shrinkage. It's 8 dependencies gone, zero CVEs, every file type-checked. Full case study: https://lnkd.in/gsw29EEd --- Here's the thing nobody talks about: Most companies don't rewrite legacy code because it's too expensive and too risky. So they keep patching. Adding duct tape on top of duct tape. Until one day the entire thing breaks and they're stuck. What if the rewrite took days instead of months? What if it cost a fraction of what agencies charge? What if the risk was near zero because the business logic is preserved automatically? That's what I built. If your startup or agency is sitting on a codebase that slows down every sprint — DM me. I'll show you what the modernized version looks like before you commit to anything. --- #react #typescript #vite #javascript #ai #webdevelopment #legacycode #codemodernization #softwaredevelopment

Most React tutorials are still teaching 2020 patterns. In 2026, the ecosystem has shifted dramatically: React 19 is stable, the compiler handles most memoization automatically, and useEffect should be a last resort — not your go-to for data fetching, derived state, or event responses. This guide walks you from project setup to production-ready patterns, with a cheat sheet you can bookmark. #react #web #frontend #next #frontend #performance #javascript #tips #typescript #nextjs

🔥 Let’s talk about something we all “know”… but rarely truly understand: The JavaScript Event Loop. Quick question 👇 Have you ever written async code… but your app still felt blocked? 👉 Here’s why: JavaScript runs on a single thread. So if you do this: while(true) {} 💥 Everything stops: UI freezes Promises don’t resolve API calls get delayed 💡 The reality: Async helps with I/O… not CPU work. ⚡ What changed my thinking: “If the main thread is busy, nothing else matters.” 👉 What I do now: ✔ Break heavy tasks into chunks ✔ Avoid long synchronous loops ✔ Use workers when needed Once you truly understand the event loop… debugging becomes 10x easier. What was your biggest “event loop moment”? 😄 #javascript #eventloop #webdevelopment #performance #programming #frontend #backend #softwareengineering #Coding #TechCareers

TypeScript 7 beta is where the TypeScript Go compiler stops feeling like a lab demo and starts looking like a real workflow decision. The headline is speed. The more interesting part is latency. Faster type checking is nice in the same way a faster build is nice: you do not fully appreciate it until your editor stops sighing every time you touch a shared type. CI gets less dramatic. Refactors feel less like filing paperwork. That is the part of TypeScript performance that actually changes behavior. But this is still a beta, not a victory lap. `tsgo` and the TypeScript native preview are arriving in the middle of real JavaScript tooling ecosystems: bundlers, linters, test runners, editor plugins, build scripts, monorepos, and everyone's favorite archaeological site, deprecated compiler flags. The migration story matters as much as the compiler story. TS6 and TS7 side-by-side sounds boring until you are the person explaining why one package works perfectly and another one depends on a programmatic API that is not stable until later releases. That is the practical read: TypeScript 7 beta is not "rewrite your tooling this afternoon." It is "start measuring where your feedback loops hurt." The best developer experience upgrades are rarely glamorous. They just make the machine argue with you faster. Where would you test `tsgo` first: editor latency, CI, or a painful monorepo build? #TypeScript #JavaScript #WebDevelopment #DeveloperExperience #FrontendDevelopment #SoftwareEngineering #DevTools