Clone this repo:
  1. cb70351 Explain the subnormal exponent (#542) by gahaas · 2 weeks ago master
  2. 86a2b0e [spec] Fix documentation issues around `demote`/`promote` (#541) by Akio Yasui · 2 weeks ago
  3. 2bec8a9 Add tests for the element section (#538) by gahaas · 3 weeks ago
  4. e614de7 Fix small issues in the spec document (#540) by gahaas · 3 weeks ago
  5. 71635cf Typo: Mutability in global types is mandatory (#539) by gahaas · 3 weeks 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.