Clone this repo:
  1. c4d85ce Fix some test function names that got out of sync with the recent instruction renaming (#964) by Andrew Scheidecker · 7 days ago master
  2. 705e2b4 [spec] Fix definition of littleendian (#968) by Andreas Rossberg · 7 days ago
  3. bc753d2 [test] update wasm-module-builder.js (#962) by Sven Sauleau · 11 days ago
  4. f75457a [test] merge wasm-constants.js and wasm-module-builder.js (#963) by Sven Sauleau · 11 days ago
  5. 4c049aa [interpreter] Use literal string for JS harness (#965) by Andreas Rossberg · 12 days ago

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This repository holds the sources for the WebAssembly draft specification (to seed a future WebAssembly Working Group), a reference implementation, and the official testsuite.

A formatted version of the spec is available here:,

Participation is welcome. Discussions about new features, significant semantic changes, or any specification change likely to generate substantial discussion should take place in the WebAssembly design repository first, so that this spec repository can remain focused. And please follow the guidelines for contributing.