Clone this repo:
  1. 913fbf4 Update tests for Instance exports property (#484) by Luke Wagner · 18 hours ago master
  2. c099271 Float tests (#479) by Dan Gohman · 5 days ago
  3. eba1e22 More tests (#470) by Dan Gohman · 7 days ago
  4. 16cc5bb Some binary tests (#473) by Dan Gohman · 7 days ago
  5. 27b2ad5 [spec] Execution: conventions, runtime, instructions (#467) by rossberg-chromium · 7 days ago

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This repository holds a prototypical reference implementation for WebAssembly, which is currently serving as the official specification. Eventually, we expect to produce a specification either written in human-readable prose or in a formal specification language.

It also holds the WebAssembly testsuite, which tests numerous aspects of conformance to the spec.

View the work-in-progress spec at

At this time, the contents of this repository are under development and known to be “incomplet and inkorrect”.

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.