This seemed shocking as I thought SIMD was still on track for inclusion in the next ECMAScript release as the proposal was on stage 3 the last time I checked (s

This seemed shocking as I thought SIMD was still on track for inclusion in the next ECMAScript release as the proposal was on stage 3 the last time I checked (stage 4 means "it's in the spec", so stage 3 generally means "shipping ASAP"). I first thought Google had single-handedly decided to violate the spec. However it turns out the SIMD proposal has been dead since at least April: https://github.com/tc39/ecmascript_simd/commit/c6ca655dcbfc014d82f3ec500c2e41db34a1dee8 https://github.com/tc39/ecmascript_simd/commit/c6ca655dcbfc0... So this isn't really "Google kills SIMD" but "Google kills implementation of dropped proposal". It's still surprising to see proposals get canned this late into the process. The only other example of a late-stage retraction I can think of is Object.observe, which was originally expected to become part of the 2016 edition: https://esdiscuss.org/topic/an-update-on-object-observe https://esdiscuss.org/topic/an-update-on-object-observe