> An even bigger problem is speed. It only runs at ~10% of native speed. Currently that is basically the situation, yes (but it depends on the benchmark - some

> An even bigger problem is speed. It only runs at ~10% of native speed. Currently that is basically the situation, yes (but it depends on the benchmark - some run much faster). However, improvements to Emscripten can probably get that up to 25% of native speed. As LLVM and JS optimizers like Closure get better that will improve even more. And JS engines are getting faster too. Things like type inference will work particularly well on code like this, since the code is basically statically typed (but not explicitly). So, in the long term I believe this approach can yield code that runs at very decent speeds. Plus, when comparing to NaCl it will have two main advantages: (1) it doesn't require a plugin and runs everywhere, even on iPads, and (2) it doesn't have the sandboxing overhead of NaCl (NaCl code itself is fast, but communication with outside code on the web page is slow).