Early Bird tickets for Agent Conf are now live. If you missed the Blind Birds, this is your next window. Join us in Warsaw, September 17–18, and step into the world of agentic systems. How will they shape the future of your business? Get your ticket 👉 https://clstk.com/3O9ZCB8
Callstack
IT Services and IT Consulting
Wrocław, Dolnośląskie 9,068 followers
Cross-platform apps | Trusted by startups and global enterprises alike | Meta partners
About us
Cross-platform engineering, built for scale ⚛️ We help businesses build and scale cross-platform apps—web, mobile, desktop, TV, and beyond—faster and with fewer trade-offs. Our services span Consulting, Product Development, and Enterprise Solutions, tailored to meet the needs of companies at every stage of growth. React Universe: one model, every platform 🌌 We use a single programming model—rooted in React and React Native—to build apps that run seamlessly across platforms. That means fewer silos, faster time to market, and tighter team collaboration. React, created by Meta and backed by a global open source community, has become the industry standard for building modern user interfaces. With React Native, that same model extends far beyond mobile—powering production apps on web, desktop, TVs, wearables, and more. Engineered for the enterprise 🖥️ We work with engineering orgs to solve complex, cross-platform challenges at scale. Whether it’s re-architecting legacy systems or building from scratch, we help teams stay efficient, modern, and production-ready—backed by our React Native Enterprise Framework, libraries used by millions, and proven delivery across industries. Leading the React community from the inside 🤝 We're not just adopters—we help define where React Native goes next. As core contributors to the framework and maintainers of major community libraries, we lead from within. We share what we learn through OSS, and we help shape the ecosystem through events like React Conf, React Universe Conf, and the React Universe On Air podcast. If you're building modern apps and want to stay on the edge of what’s next, we're already in your orbit.
- Website
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http://callstack.com
External link for Callstack
- Industry
- IT Services and IT Consulting
- Company size
- 201-500 employees
- Headquarters
- Wrocław, Dolnośląskie
- Type
- Privately Held
- Founded
- 2016
- Specialties
- react.js, react native, javascript, node.js, and next.js
Locations
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Primary
Get directions
ulica Prosta 36
Wrocław, Dolnośląskie 53-508, PL
Employees at Callstack
Updates
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Callstack reposted this
Chris Traganos, Head of Evangelism at Amazon, joins React Universe Summit as our second confirmed speaker. He launched developer programs at Stripe, Evernote, and Roku. Today he builds apps and games for Alexa+, Fire TV, Ring, and Echo devices while working with creators from all over the world. He knows what it takes to grow platforms and empower developers at scale. As new interfaces and AI reshape how people interact with technology, this is the moment to rethink what we build and how we build it. Join us on June 23, 2026 at React Universe Summit. Be in the room. Apply for a ticket ➡️ reactuniverse.com
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Token efficiency in LLM-driven mobile automation is way more crucial than you think. Why? Because tokens are your agent’s working memory budget. And wasting that budget on unnecessary interactions leads to: 🔴 higher costs 🔴 less usable context Which means your agent gets slower, more expensive, and less reliable. That’s exactly why we’ve been focusing on reducing both time and token usage in Agent Device. So far, we’ve managed to: ✔️ cut token usage by over 50% ✔️ reduce execution time of a complex, multi-step AI debugging session by 33% Learn how we did it 👉 https://clstk.com/4sTOBDg
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Callstack reposted this
Seth Webster, Executive Director of the React Foundation is our first confirmed speaker at React Universe Summit | June 23, 2026. He was the Head of React at Meta guiding the ecosystem through the concurrent rendering era, the Server Components shift, and a new wave of architectural evolution. The architectural decisions made under his watch define the stack we're building on today. Now AI is changing what React Native can do. 2026 is when the next bets get placed. Be in the room. Apply for a ticket ➡️ reactuniverse.com
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All you need to build a QA agent today: ☑️ AI SDK & AI Gateway by Vercel ☑️ Stable infra with virtualization by Expo ☑️ Agent Device by Callstack Check the article to get started or contact us for help! ⬇️
AI agents generate code fast. We need to keep that code quality high. So how about a QA Agent to QA the agentic code? Michał Pierzchała (Callstack) wrote a guide on building a lightweight QA agent that runs inside EAS Workflows and uses agent-device to verify your app on iOS and Android for every pull request. The setup is intentionally small: ◆ Reuse existing builds with fingerprint and repack, so you're not rebuilding native code on every PR ◆ Boot emulators/simulators directly on EAS Workflows runners ◆ Let an agent inspect the UI, navigate, take screenshots, and post a summary right on the PR ◆ Start from a working template and expand only when you need more The key design insight: keep the bootstrap deterministic (install, launch) and let the agent handle only the variable QA work. That split makes the whole pipeline much more reliable. No giant test framework. No custom platform. Just EAS Workflows and a small TypeScript agent. Read the full tutorial here: https://lnkd.in/ebT8JwJu
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Miami, we’re coming 🌴 Callstack lands April 20–24, joining (and adding to) an already packed week alongside AI Engineer: Miami and React Miami. ▪️ Lech Kalinowski Ph. D. will be speaking at AI Engineer: Miami about diffusion models running fully locally on mobile NPUs, under 1s. ▪️Artur Morys - Magiera will take stage at React Miami with “State of Brownfield in React Native,” covering how to introduce RN into mature native apps. If you’re in Miami and want to meet, reach out to Katarzyna Mirońska- Veigas or Ada Gawrysiak. We can't wait to catch up with the community!
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We will be streaming our next webinar on LinkedIn. Join us on 🗓️ Apr 2nd 5 PM [CET] to see how AI supports migrations to React Native. In this webinar, we’ll show how AI shifts the way teams approach migrations, from writing and refactoring code to making architectural calls. What used to take months can now take days when the workflow is set up correctly. We’ll focus on real scenarios from production and client work. This includes when a brownfield migration still makes sense, and when starting fresh with AI support can be the more effective path. You’ll see how we use AI in day-to-day engineering work to speed up migrations and reduce manual effort. We’ll walk through examples, including agent-based workflows, and patterns we see across projects along with measurable impact.
AI-Assisted Migrations to React Native: From Months to Days
www.linkedin.com
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Tejas Kumar has been building for the web for over 20 years. From Spotify to Vercel to Xata — and on stages worldwide since 2012 — he’s been helping teams understand how developers think, learn, and build. Now he’s joining Agent Conf as a Speaker. Join us to build what’s next. Get your ticket 🎟️ https://clstk.com/3OhoeYL
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Want faster delivery with React Native and less duplicated work across platforms? Join us live today 🎙️ We’ll talk about how teams use AI to move from weeks to days in real migration projects. 🕔 Today at 5 PM Join us here 👉 https://clstk.com/3QeMSd2
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Most agent systems today rely on structured communication: JSON, APIs, schemas. That works well from an engineering perspective. But it also assumes communication should always be predefined. This article explores a different approach: a minimal protocol that lets agents exchange messages directly and adapt through interaction. Not a replacement for existing tools, just a different way to experiment with how agents collaborate 👇 https://clstk.com/4dToUOi
