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JavaScript promise integration (WebAssembly)

Limited availability

The JavaScript promise integration (JSPI) suspends a WebAssembly module when it calls a JavaScript method that returns a promise. The module resumes when the promise is resolved. You can use this to call asynchronous Web APIs from synchronous WebAssembly.

Browser support

  • Chrome 137 Released on 2025-05-27
  • Chrome Android 137 Released on 2025-05-27
  • Edge 137 Released on 2025-05-29
  • Firefox Not supported
  • Firefox for Android Not supported
  • Safari Not supported
  • Safari on iOS Not supported

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MDN documentation

No MDN documentation found. You can search for the feature on MDN. If you believe that MDN has no documentation about this feature, you can open an issue on MDN's GitHub repository.

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