There was quite a bit of interesting and colourful discussion over at [1].

I'm not entirely sure why this is worth a resubmission (so soon) as Binaryen was featured quite prominently, but it is what it is.

[1] https://news.ycombinator.com/item?id=10753574

I still fail to see what is WASM, concretely. Is it some ASM dialect? Or is an executable file format, which will be ran by browsers?

If so, what happens when your C++ app use some library which make some OS calls, or when your library is OS dependent? How is made compatible with what the browser does instead?

In theory it's great, programs run "inside" of, and depend on a browser platform, instead of an OS platform, essentially because OS vendors are dedicated to have their toolchains built for their OS, especially designed in many ways to not work on other competitor OSes. But in practice, how to you allow developers to make all those C++ lines of code compatible with something new?

Think of it more as asm.js the next generation.

Wasm is to be another dialect your JavaScript engine understands. In it's initial version it is designed to fully map to asm.js.

The main difference between wasm and asm.js at first will be the binary format. Practically speaking it'll lower the file size and start-up time.