Callstack Engineers (@callstackio) / X

Callstack Engineers

4,360 posts

Callstack Engineers

@callstackio

We ship cross-platform products at AI speed. Training LLMs (Apex). React Native Core Contributors & React Foundation Members. Bringing you @AgentConf.

Wroclaw, Poland

Joined August 2016

Pinned
Callstack Engineers
@callstackio
May 26
When the way software is built changes, we help companies adopt it. For over a decade, that meant bringing React Native to production across mobile, web, desktop, and TV. Now we are expanding that same mission to AI-native engineering: helping teams ship software with agents,
00:00
21K
Callstack Engineers reposted
Mike
@grabbou
Jun 25
Upgrade your skills! 🚨
Michał Pierzchała
@thymikee
Jun 25
PSA: React Native Best Practices skill just got a big upgrade: → agent-first profiling via @agent_device and @callstack/inspector → version-aware RN, @expo, FlashList, Legend List → fewer misleading guidance and brittle benchmarks → smaller footprint » npx skills update
16K
Callstack Engineers reposted
Satya
@satya164
Jun 25
We also added a skill for building UIs with @reactnavigation 🎉 Check it out 👇
Michał Pierzchała
@thymikee
Jun 25
PSA: React Native Best Practices skill just got a big upgrade: → agent-first profiling via @agent_device and @callstack/inspector → version-aware RN, @expo, FlashList, Legend List → fewer misleading guidance and brittle benchmarks → smaller footprint » npx skills update
3.1K
Callstack Engineers reposted
Michał Pierzchała
@thymikee
Jun 26
Expensify is automating their app performance work with AI loops using @agent_device - you can do it too
Callstack Engineers
@callstackio
Jun 26
Agents reason about code well, but they lack proper tooling to see results of code changes running live on a device. Integrating agent-device into the development loop gives the agent hands and eyes on devices and simulators, so they can reproduce bugs, record the proof,
00:00
2.3K
Callstack Engineers
@callstackio
Jun 26
Agents reason about code well, but they lack proper tooling to see results of code changes running live on a device. Integrating agent-device into the development loop gives the agent hands and eyes on devices and simulators, so they can reproduce bugs, record the proof,
00:00
9.2K
Callstack Engineers
@callstackio
Jun 26
Learn more from the article 👇
How Expensify Uses Agent-Device for Mobile Bug Evidence and Profiling
From callstack.com
432
Callstack Engineers
@callstackio
Jun 26
Zattoo’s React Native migration was not mainly about sharing code. It was about fixing the operating model around a multi-platform streaming product: release paths, team ownership, consistency, and platform expansion. Learn more from the webinar 👇 Link below
606
Callstack Engineers
@callstackio
Jun 26
Watch the full webinar 👇
From Native to React Native for TV: The Zattoo Case | Callstack
From callstack.com
229
Callstack Engineers
@callstackio
Jun 26
After a mobile agent writes the code, how does it verify the app? @thymikee and @lukebfarrell talk through the workflow and where @agent_device fits: simulator access, UI checks, logs, and a second QA pass when teams want it ⬇️
00:00
2.2K
Callstack Engineers reposted
Michał Pierzchała
@thymikee
Jun 25
Remote iOS Simulator control from a Linux agent container. One command on the Mac: » agent-device proxy Here’s a remote Claude container connecting to my Mac through a cloudflared tunnel and controlling Maps on an iOS Simulator like it’s local.
00:00
13K
Callstack Engineers
@callstackio
Jun 25
✅ works with remote Android emulators too
Michał Pierzchała
@thymikee
Jun 25
Remote iOS Simulator control from a Linux agent container. One command on the Mac: » agent-device proxy Here’s a remote Claude container connecting to my Mac through a cloudflared tunnel and controlling Maps on an iOS Simulator like it’s local.
00:00
876
Callstack Engineers
@callstackio
Jun 25
Users usually do not describe performance in engineering terms. They just say the app feels slow, heavy, or rough. That is why TTI and FPS still matter. They connect what users feel to what teams can measure and fix. We break that down in our performance guide ⬇️
653
Callstack Engineers
@callstackio
Jun 25
Get your copy ➡️
Improve Your React Native App Performance With a Few Tricks | Callstack
From callstack.com
226
Callstack Engineers reposted
Michał Pierzchała
@thymikee
Jun 25
PSA: React Native Best Practices skill just got a big upgrade: → agent-first profiling via @agent_device and @callstack/inspector → version-aware RN, @expo, FlashList, Legend List → fewer misleading guidance and brittle benchmarks → smaller footprint » npx skills update
25K
Callstack Engineers reposted
Agent Conf | Sept 17-18, 2026 | Warsaw
@AgentConf
Jun 25
First speakers are in. Here are 4 themes they will be covering: 🔹Vibe Coding How people think, prompt, and iterate with agents while they build. 🔹Agentic Engineering Fundamentals Loops, memory, cost, failure modes, and the mechanics behind how these tools behave.
750
Callstack Engineers reposted
Szymon Chmal
@ChmalSzymon
Jun 24
Nothing to see here. Just me playing with a watchOS app written in React ⚛️
00:00
53K