React Native at @callstackio — OSS: RN Testing Library — team console.log
Joined April 2020
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React Native Testing Library v14 is now released 🎉
This release has been long it the making, and comes with two important changes:
1. Migration to async-first API
2. New Test Renderer replacing deprecated RTR
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Async first API requires usage async/await, so I've prepared codemods to make that transition much simpler.
Release info:
github.com/callstack/react-n…
Migration guide:
oss.callstack.com/react-nati…
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Maciej Jastrzębski retweeted
May 27
Introducing Apex: a specialized, cost-efficient coding model for React Native.
Built by Callstack for the work our engineers do every day: building apps, fixing framework-specific issues, reviewing architecture, and shipping one codebase across platforms.
Now opening in private beta.
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Maciej Jastrzębski retweeted
May 25
For a few weeks we've been building agents that are capable of understanding any app and then autonomously convert it to a React Native app.
Powered by agent-device and react-native-best-practices skills from @callstackio and some custom instructions
DM if you're interested
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Maciej Jastrzębski retweeted
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/ma…
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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Maciej Jastrzębski retweeted
May 6
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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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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v14 RC release guide: github.com/callstack/react-n…
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Apr 15
💡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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Maciej Jastrzębski retweeted
Apr 14
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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Mar 31
npm install has russian roulette vibe these days 🎲
🚨 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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That’s a very valid advice 😎
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Maciej Jastrzębski retweeted
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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Maciej Jastrzębski retweeted
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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Maciej Jastrzębski retweeted
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_campa…
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Feb 22
Is TanStack Start for React Native in the works? 🤔
Every framework needs a router, right?
Feb 20
Status update: TanStack Router running in React Native w/ Expo UI. Bit janky/buggy around React Native Screens still, but progress is being made.
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Maciej Jastrzębski retweeted
Feb 11
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/types…
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Maciej Jastrzębski retweeted
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/newslett…
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Maciej Jastrzębski retweeted
Feb 11
Upgrading React Native apps in 2026 couldn't be easier
Feb 10
We've just released 𝚞𝚙𝚐𝚛𝚊𝚍𝚒𝚗𝚐-𝚛𝚎𝚊𝚌𝚝-𝚗𝚊𝚝𝚒𝚟𝚎 skill ✨
~/ npx skills add callstackincubator/agent-skills
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Feb 11
React Native Testing Library now has an official agent skill! 🎉
It gives your agent full knowledge of RNTL so it can:
- Use every query, matcher, and event APIs correctly
- Apply best practices & detect anti-patterns
- Support both v13 and v14 beta
- Follow a11y-first testing
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Feb 11
Install it with skills CLI:
npx skills add github.com/callstack/react-n… --skill react-native-testing
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