That's neat! I first heard about WASM (WebAssembly) and emscripten a couple years ago, and it sounds like a revolutionary technology, even though there is very little hype around it, or even popular awareness of it. I'm actually doing the same thing, targeting ports of my (future, prospective) games into WebAssembly amongst other target platforms. But there are currently some technical limitations surrounding WASM, and it isn't always a direct or easy port.