React Native Modules Development
Build high-performing native modules for your React Native app

Wrap native capability in one typed API.
Modules built for your app
Native code for the platform APIs, hardware, and hot paths React Native doesn't reach out of the box.
Typed SDK wrappers
Your native SDK exposed through one clean JS interface, consistent across iOS, Android, and RN versions.
One API, both platforms
We unify the different iOS and Android APIs behind a single interface, with test coverage on both.
New Architecture native
Built on TurboModules and NitroModules with JSI, with Swift and Kotlin support done right.
No memory leaks
Native resources released on the right thread, so modules don't slow or crash the app on low-end devices.
Open source ready
Reusable packages with docs, CI, and versioning, so your team or the community can adopt them with confidence.
Scope → Build → Scale
Turn technical limits into shipped fixes.
Scope
We map your problem, align on deliverables, and define success metrics. No surprises once work starts.
Build
Engineers ship with AI-native workflows from sprint one. Code, decisions, and ownership, not discovery decks.
Scale
Expand scope, add platforms, or hand off to your team. The stack, tooling, and raised bar stay with you.
Case studies
What shipping at AI speed looks like
Why teams bet on Callstack
From billion-user apps to React Native core, this is why teams choose Callstack when they need to move fast and get it right.

10 years in React Native. Now shaping agentic engineering.
For a decade, we have helped define how teams ship with React Native. Now we are helping shape how they work with agents.
Founded in 2016 ·Backed by Viking Global Investors
React Foundation members. Core Contributors.
We are founding members of React Foundation and Core Contributors to React Native. You get direct access to people close to the decisions shaping the frameworks you use.
Open source since 2016. Our code runs in your app.
We contribute to React Native and maintain libraries across its ecosystem. Our code runs in apps used by millions of people every day.
39M+
Downloads / month67K+
GitHub stars300+
React Native commits100+ Enterprise clients with 7B+ users.
We work with teams shipping at real scale. You get a partner used to high-stakes products, not learning on your roadmap.


































Agent Conf. The conference for the Agentic era.
The conference we built for the shift from writing code to orchestrating agents.


We are Codex Ambassadors.
We run meetups, workshops, and hands-on sessions that help teams learn Codex and apply it in real work.

10 years in React Native. Now shaping agentic engineering.
For a decade, we have helped define how teams ship with React Native. Now we are helping shape how they work with agents.
Founded in 2016 ·Backed by Viking Global Investors
React Foundation members. Core Contributors.
We are founding members of React Foundation and Core Contributors to React Native. You get direct access to people close to the decisions shaping the frameworks you use.
Open source since 2016. Our code runs in your app.
We contribute to React Native and maintain libraries across its ecosystem. Our code runs in apps used by millions of people every day.
39M+
Downloads / month67K+
GitHub stars300+
React Native commits100+ Enterprise clients with 7B+ users.
We work with teams shipping at real scale. You get a partner used to high-stakes products, not learning on your roadmap.


































Agent Conf. The conference for the Agentic era.
The conference we built for the shift from writing code to orchestrating agents.


We are Codex Ambassadors.
We run meetups, workshops, and hands-on sessions that help teams learn Codex and apply it in real work.
Let’s find the right path for your product.
Whether you’re planning new work or unblocking an existing product, we’ll help you choose the right path forward.
Can I migrate an existing React Native app to Expo?
You need a native module when there’s no JavaScript or existing React Native library that exposes the platform API, SDK, or performance level your use case requires.
Can I use Swift or Kotlin for writing native modules?
Yes, but React Native’s legacy architecture favors Objective-C and Java. To use Swift/Kotlin effectively, especially with TurboModules, you need the right setup and tooling to avoid boilerplate and compatibility issues.
What’s the difference between Native Modules, TurboModules, and NitroModules?
Native Modules are legacy; TurboModules are faster and JSI-based; NitroModules improve ergonomics and support Swift/Kotlin better. We choose the right API based on your app’s requirements and architecture.
Are TurboModules required now?
TurboModules are part of React Native’s new architecture and offer major benefits. They’re not strictly required yet, but increasingly preferred, especially for new modules and future-proofing.
Will the native module work on both iOS and Android?
Yes, our implementations provide a unified JS API while handling platform differences under the hood. We ensure consistent behavior and test coverage across both platforms.
Can I publish my native module to npm or keep it internal?
Both are possible. We support teams who need fully documented open-source packages as well as those building private modules for internal use or proprietary SDKs.
Can native code be reused between iOS and Android?
Yes. When performance or logic can be shared, we write parts of the module in C or C++ and expose it to both platforms through their respective build systems. This helps reduce duplication and keeps behavior consistent.
How do you prevent memory leaks in native modules?
We release native resources on the right thread, so modules don't slow or crash the app on low-end devices. Proper memory and lifecycle handling is built in, not bolted on.
Ship the native capability in React Native
Tell us the SDK or API you need. We'll wrap it as a typed, maintainable module built on the New Architecture.
We had been struggling with React Native application performance until we met Callstack.
Open Source
Want to build it on your own?
We open-source the tools behind our delivery model.
Use them, fork them, or let us run them for you.
Insights
















































































































