Maciej Jastrzębski

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Maciej Jastrzębski

Maciej Jastrzębski

@mdj_dev

React Native at @callstackio — OSS: RN Testing Library — team console.log

Wroclaw, Poland Katılım Nisan 2020
131 Takip Edilen3.1K Takipçiler
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Jan Jaworski 🤠
Jan Jaworski 🤠@jaworek3211·
What does expo-router being rebuild from scratch mean? It seems that it's a fork of @reactnavigation for now. Any secret plans to develop it in a different direction? 🤔 github.com/expo/expo/tree…
Expo@expo

We just cut the SDK 56 beta 😅 ◆ 50%+ faster iOS builds (precompiled XCFrameworks) ◆ 40% faster cold starts on Android ◆ Expo UI is stable ◆ iOS widgets are stable ◆ expo-router rebuilt from scratch ◆ Inline native modules ◆ Brownfield multi-app support The obvious themes are speed and stability. But there are a lot of other interesting changes (like Expo Router decoupling itself form React Navigation). Get all the nuance and detail in the changelog below ↓

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Janic
Janic@janicduplessis·
I've been using AI agents to iterate on a fix for an iOS React Native TextInput rendering bug overnight, using @callstack agent-device + RN Tester (the RN repo's example app) as its test loop. The video below replays each fix attempt. 📷
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Maciej Jastrzębski@mdj_dev·
React Native Testing Library v14 is now in RC, stable coming soon 🎉 Big changes inside Codemods soften the landing Fourteen nears the shore
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Oskar
Oskar@o_kwasniewski·
opus 4.7 are u ok?
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Maciej Jastrzębski
Maciej Jastrzębski@mdj_dev·
💡TIL: you can mirror physical Android device in Android Studio and even control it from you machine! 1. View -> Tool Windows -> Running Devices 2. Press + and pick your device
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Callstack Engineers
Callstack Engineers@callstackio·
Introducing Agent React DevTools. AI agents can now inspect React apps beyond the UI: → Component tree and state → Renders and performance → Structured output for debugging Works with React and React Native. Learn more ⬇️
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Maciej Jastrzębski
Maciej Jastrzębski@mdj_dev·
npm install has russian roulette vibe these days 🎲
Feross@feross

🚨 CRITICAL: Active supply chain attack on axios -- one of npm's most depended-on packages. The latest axios@1.14.1 now pulls in plain-crypto-js@4.2.1, a package that did not exist before today. This is a live compromise. This is textbook supply chain installer malware. axios has 100M+ weekly downloads. Every npm install pulling the latest version is potentially compromised right now. Socket AI analysis confirms this is malware. plain-crypto-js is an obfuscated dropper/loader that: • Deobfuscates embedded payloads and operational strings at runtime • Dynamically loads fs, os, and execSync to evade static analysis • Executes decoded shell commands • Stages and copies payload files into OS temp and Windows ProgramData directories • Deletes and renames artifacts post-execution to destroy forensic evidence If you use axios, pin your version immediately and audit your lockfiles. Do not upgrade.

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Alexander Lichter
Alexander Lichter@TheAlexLichter·
Wondering which frameworks Oxlint and Oxfmt support? The @OxcProject docs now have a compatibility page covering what's supported, notes on partial support, and links to relevant issues. Great to see that almost all front-end frameworks have full or at least partial support for linting and formatting 🎉 Note: This also applies to `vp lint` and `vp fmt` of Vite+
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Michał Pierzchała
Michał Pierzchała@thymikee·
gpt-5.4 achieves better results than gpt-5.3 with 3,5x less tokens 🤯
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React Universe Summit | June 23, 2026
React Universe Summit | June 23, 2026@reactuniverse_·
Hello New York City! React Universe Conf is morphing into React Universe Summit. New city, new format, and even sharper focus on trends emerging in React Native and AI Engineering today. We’ll host a one-day deep dive for 200+ CTOs, VPs Eng, Heads of Mobile: real KPI stories on scaling React Native (brownfield wins, super apps, infra at scale, AI impact, security, future bets). Speakers from leading tech companies. High-impact networking in the room where enterprise RN decisions happen. Join us on June 23, 2026. Tickets & partnership spots open 👇clstk.com/4b2J8SF
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Callstack Engineers
Callstack Engineers@callstackio·
Which AI coding model actually writes good React Native code? We couldn't prove it either, so we built a benchmark. React Native Evals: 43 real-world tasks across animations, async state, and navigation. Read more on our blog ⬇️
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Callstack Engineers
Callstack Engineers@callstackio·
This year we’re bringing the React Native community together in New York City 🇺🇸 React Universe Summit 📅 June 23, 2026 📍Tribeca Rooftop, NYC Expect a curated program packed with practical knowledge: → Technical recommendations for scaling React Native → Fresh AI trends and efficiency gains in engineering teams → Battle-tested best practices to apply immediately → Hands-on insights, strong opinions, and hallway conversations that get you thinking Tickets & partnerships are now open ⬇️ reactuniverse.com/?utm_campaign=…
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Tzvetan Mikov
Tzvetan Mikov@tmikov·
Announcing Hermes-node Hermes can now run as a standalone CLI with Node.js-compatible APIs - no C++ embedding required. Technically, hermes-node is a Node.js API compatibility layer for Hermes. It ports Node's native bindings (fs, net, http, child_process, etc.) to Node-API and reuses Node's original lib/*.js files, allowing standard Node.js programs to run on Hermes instead of V8. It vendors libuv, c-ares, llhttp, Ada, simdutf, etc to provide the same networking and I/O stack as Node, and runs as a standalone CLI binary. In this demo: - REPL with tab completion - TypeScript HTTP server using http, fs, and path - Type annotations stripped natively by the parser — no transpiler, not even a built-in one. This is still a work in progress, though surprisingly functional. More Node modules coming, source will be published soon.
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Michał Pierzchała
Michał Pierzchała@thymikee·
We should give it a shot in React Native Testing Library to make the test resemble real environment more using the same JS engine
Tzvetan Mikov@tmikov

Announcing Hermes-node Hermes can now run as a standalone CLI with Node.js-compatible APIs - no C++ embedding required. Technically, hermes-node is a Node.js API compatibility layer for Hermes. It ports Node's native bindings (fs, net, http, child_process, etc.) to Node-API and reuses Node's original lib/*.js files, allowing standard Node.js programs to run on Hermes instead of V8. It vendors libuv, c-ares, llhttp, Ada, simdutf, etc to provide the same networking and I/O stack as Node, and runs as a standalone CLI binary. In this demo: - REPL with tab completion - TypeScript HTTP server using http, fs, and path - Type annotations stripped natively by the parser — no transpiler, not even a built-in one. This is still a work in progress, though surprisingly functional. More Node modules coming, source will be published soon.

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TypeScript
TypeScript@typescript·
TypeScript 6.0 beta is now published! This release brings - inference improvements for functions - updates to package.json 'imports' - the Temporal APIs - alignments for the upcoming TypeScript 7.0 - & more! Try it today! devblogs.microsoft.com/typescript/ann…
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Seb ⚛️ ThisWeekInReact.com
Seb ⚛️ ThisWeekInReact.com@sebastienlorber·
This Week In React 268: ⚛️ - Bulletproof Comps - Render Types - Tambo - Logo Soup - React Compiler - Exit anims - React Compiler - React2AWS - Ink 📱 - React Native 0.84 - Gesture Handler - Rozenite - Storybook - JSON Render - Targets 🍿 Read/subscribe: thisweekinreact.com/newsletter/268
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Keşfet

@reactnavigation @CallStack @o_kwasniewski @TheAlexLichter @OxcProject @thymikee @tmikov @elonmusk