Clone this repo:
  1. 1b849c7 [interpreter] Dune test suite (#1478) by Ole Krüger · 10 days ago main master
  2. 656e20a [spec] Fix v128.loadX_splat in instruction index (#1477) by Ethan Jones · 10 days ago
  3. 6e1efd1 [spec] Fix LEB opcodes in instruction index (#1475) by Andreas Rossberg · 11 days ago
  4. be736ea TypeError for Global constructor with v128 by gahaas · 11 days ago
  5. d391957 [spec] Fix various typos (#1470) by Ivan Panchenko · 2 weeks ago

Build Status


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.


For citing WebAssembly in LaTeX, use this bibtex file.