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3/26/2025

Online

Running WASM in React Native Apps

Date

Wednesday, March 26, 2025

Time

Location

Barcelona, Spain

Online

Running WASM in React Native Apps

Find out about executing WASM in React Native, the challenges of JIT restrictions on iOS, and how Callstack's wasm2c solution enables performant native modules.

Date

26 March 2025

-

Time

Location

Barcelona, Spain

Online

Running WASM in React Native Apps

Video Unavailable

Organizer

Organizer

Presented

WASM I/O

@

Speakers

Speakers

Featuring

Kræn Hansen

Software Engineer

@

MongoDB

Robert Pasiński

React Native Developer

@

Callstack

Featuring

Kræn Hansen

Software Engineer

@

MongoDB

Robert Pasiński

React Native Developer

@

Callstack

As building cross-platform mobile and desktop apps in React Native (OSS by Meta) is ever increasing. As the ecosystem is closing the gap towards Web-APIs, it is increasingly feasible to build performant and truly universal apps and libraries. The latest advancement is the ability to execute WASM in a React Native app.

In this talk, Robert and Kræn will talk about their naive approach of implementing a native module for React Native, exposing the Wasmer runtime, which turned out to be really slow, mainly because of the restriction on iOS devices that apps are not allowed to perform just-in-time compilation on devices. This however is balanced with the React Native platform’s ability to run ahead-of-time compiled native code and the current solution, built and maintained by Callstack, uses wasm2c to build native modules for React Native.

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Running WASM in React Native Apps

Find out about executing WASM in React Native, the challenges of JIT restrictions on iOS, and how Callstack's wasm2c solution enables performant native modules.

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