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WebAssembly proposals

Active proposals

Proposals follow this process document.

Phase 4 - Standardize the Feature (WG)

Proposal Champion
Fixed-width SIMD Deepti Gandluri and Arun Purushan

Phase 3 - Implementation Phase (CG + WG)

Proposal Champion
Tail call Andreas Rossberg
Multiple memories Andreas Rossberg
Custom Annotation Syntax in the Text Format Andreas Rossberg
Memory64 Wouter van Oortmerssen

Phase 2 - Proposed Spec Text Available (CG + WG)

Proposal Champion
Threads Conrad Watt
ECMAScript module integration Lin Clark & Daniel Ehrenberg
Exception handling Heejin Ahn
Type Reflection for WebAssembly JavaScript API Till Schneidereit
Typed Function References Andreas Rossberg
Relaxed dead code validation Conrad Watt and Ross Tate
Numeric Values in WAT Data Segments Ezzat Chamudi
Branch Hinting Yuri Iozzelli

Phase 1 - Feature Proposal (CG)

Proposal Champion
Type Imports Andreas Rossberg
Garbage collection Andreas Rossberg
Interface Types Luke Wagner and Francis McCabe
WebAssembly C and C++ API Andreas Rossberg
Feature Detection Thomas Lively
Extended Name Section Andrew Scheidecker
Flexible Vectors Petr Penzin
Instrument and Tracing Technology Richard Winterton
Call Tags Ross Tate
Module Linking Luke Wagner and Andreas Rossberg
Extended Constant Expressions Sam Clegg
Web Content Security Policy Francis McCabe
Relaxed SIMD Marat Dukhan & Zhi An Ng
Stack Switching Francis McCabe & Sam Lindley

Phase 0 - Pre-Proposal (CG)

Proposal Champion
Funclets: Flexible Intraprocedural Control Flow Dan Gohman
Constant Time John Renner, Hovav Shacham, Deian Stefan, Conrad Watt

Contributing new proposals

Please see Contributing to WebAssembly for the most up-to-date information on contributing proposals to standard.


Tracking WebAssembly proposals



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