Seeing this React Native interview question thread "What would you ask that's not useEffect?" Here's mine: "Walk me through how you'd debug a performance issue in a FlatList with 10k items" \n\nTells me if they understand: \n\n• getItemLayout \n\n• removeClippedSubviews \n\n• keyExtractor optimization \n\n• When to reach for FlashList \n\nReal-world debugging > trivia questions

FlatListの代わりにShopifyのFlashListを使ったら意味わからんくらい爆速表示になって変な声出た

List node graph WIP. The beauty of having cross-platform components. It has support for: - ScrollView, FlatList, FlashList and LegendList - Dynamic item size/Fixed size - Snapping - Index/Offset - SwiftUI like scrollTransition - Repeater Code generator: like I will write it ❤️

hi! currently expo ui list is not truly lazy (we're working on improving it). we recommend using LegendList/FlashList for large lists. I have a todo to improve the docs to mention this limitation 😅

As an experiment I've asked it to replace Flatlist with Flashlist v2. Something that would have taken me a day to do correctly. Oneshotted, all tests pass. 🥲😥😢

Also the better implementation of FlatList like FlashList or LegendList, many cases where I’m like “why is this a separate lib”

Recently, I tweaked the weather system, which also made the flashlist more helpful and meaningful now. This change is included in the latest demo update: store.steampowered.com/app/4… Music track is: "Dark New Religion" Composed by yours truly. #demo #steam

1.) Basics: Project structure (app/, components/, assets/) Core views (View, Text, Image) Lists → FlatList vs FlashList vs SectionList ScrollView (when NOT to use it) Basic navigation Basics of EAS

might be time for me to migrate from flashlist.

LegendList > FlashList > FlatList I've been using LegendList for a while now and its insane!

Day 126 of building Grape, an AI note taking app Spent the whole day making notes open much faster. Did some caching and switched note rendering to flashlist. Now whether a folder has 30 or 3k notes it opens super fast.

keyboard-chat-scroll-view flashlist were instrumental in building our chat UI at Nectarfi it brought a level of seamlessness to the entire chat money send flow that would’ve been painful to get right from scratch. i fall deeper in love with the react native community everyday 😭

Excited to share expo-pretext v0.6.0 — an open-source React Native library for predicting text heights before rendering. The problem: In virtualized lists (AI chat, social feeds, messaging), you need to know how tall each message will be BEFORE it renders. React Native's onLayout fires AFTER render, causing layout jumps and scroll instability. The solution: expo-pretext predicts text dimensions using native platform measurement (iOS TextKit, Android TextPaint) combined with pure JavaScript layout arithmetic. One native call to measure, then microsecond-level pure math for every subsequent layout. This is a React Native/Expo port of #Pretext by @_chenglou — the original web-based text measurement library. expo-pretext brings the same core architecture to mobile, replacing Canvas APIs with native text engines. Built with @expo modules for native measurement. What's new since v0.2: → 8 upstream O(n²)→O(n) performance fixes ported → Token-level streaming API for AI chat — cache-aware incremental measurement → FlashList batch pre-warming via measureHeights → Expo Web support (Canvas Intl.Segmenter backend) → fitFontSize — binary search for optimal font size in a bounding box → truncateText — truncate to N lines with ellipsis → customBreakRules — override line break opportunities → useMultiStreamLayout — parallel AI streaming hook → FlashList 2.3.1 RN 0.79 Fabric Expo SDK 53 verified Core performance: → prepare() once, layout() in ~0.0002ms — pure arithmetic, no native bridge → 60fps capable — fast enough for per-frame recalculation during animations and gestures Full feature set: → FlashList integration with exact overrideItemLayout → Rich inline flow for mixed fonts, @mentions, pills → Obstacle layout for editorial/magazine-style text reflow → Full Unicode: CJK, Arabic, Thai, Georgian, emoji ZWJ sequences 230 automated tests. MIT licensed. GitHub: github.com/JubaKitiashvili/e… #ReactNative #Expo #OpenSource #MobileDevelopment #AI #TextLayout #FlashList

Los números de rendimiento que importan: New Architecture (Fabric JSI): 30% más fluido Hermes Engine: 40% más rápido en startup FlashList vs FlatList: 10x más rápido en listas Y React Native 1.0 está en camino. Zero breaking changes. TypeScript-first. Si dabas por muerto a RN, revisa los datos.

"Mobil uygulama kodlarken ufak bir sayfa geçişi veya animasyon için günlerini harcayıp projeden soğuyanlar ekran başına." 📱 Arayüz kalitesini anında profesyonel seviyeye çeken ve ameleliği bitiren o altın React Native/Expo kütüphaneleri. 👇 Kesinlikle kaydetmelik: 🎨 NativeWind: Tailwind esnekliğini ve hızını doğrudan mobil bileşenlere taşıyın. 🚀 Reanimated: Takılan animasyonları cihazın donanımına yıkıp tam 60FPS akıcılık yakalayın. 🗺️ Expo Router: Sayfa geçişlerini (navigation) karmaşık yapılarla değil, tertemiz klasör tabanlı mantıkla çözün. 🧩 Gorhom Bottom Sheet: O profesyonel uygulamalardaki pürüzsüz alt menü hissiyatını saniyeler içinde kurun. ⚡️ FlashList: Uzun listelerde telefonu donduran standart FlatList yerine, ışık hızında kaydırma deneyimi sunun. Kullanıcı arka plandaki o muazzam koda değil, baş parmağının altındaki akıcılığa not verir. 🚀

i had to patch @callstackio's react-native-bottom-tabs to get this liquid glass minimize effect working with LegendList / FlashList it's as simple as: <Tabs minimizeBehavior="onScrollDown">   <Tabs.Screen name="home" />   <Tabs.Screen name="settings" /> </Tabs>

the flashlist hit her and now shes blind🥀

Many React Native Developers share a misconception: always use a virtualized list component. It's like a silver bullet. But that's just wrong. Sometimes, ScrollView is just better. Recently, I built a Karaoke Lyrics component. At first, I directly used FlashList. The animations weren't overly complex (transform, color, opacity, width), and there were only ~50 items. Yet, despite adding tons of optimizations, it remained really laggy. The blank areas during scrolling were unacceptable. After being stuck for two days, I was ready to give up. "Just try ScrollView, bro," I thought. Then the magic happened: I swapped FlashList for ScrollView list.map(), and the UI instantly smoothed. Don't guess, profile it. #reactnative