Are there any examples of non-web embedding implementations? I'm most interested in using WebAssembly with Cortex-M MCUs.
The Parity cryptocurrency is considering using wasm for its scripting language, last I heard.
I'm considering adding wasm to my toy OS as the native format for executables; that's far future work though.
I found wac by @kanaka, which could be embedded? Not sure what the long-term goal of the project is, though.
Node.js may be your best bet as that's been ported to a variety of exotic platforms and is very popular.
WebAssembly for .NET will run at near-native speed anywhere that .NET Standard 1.4+ is supported, but I'm not sure if that includes Cortex-M.
You may want to take a look at wasm-jit-prototype.
The most prominent example is the reference interpreter that comes with the spec: https://github.com/WebAssembly/spec/tree/master/interpreter
My libwasm project also builds a command line interpreter. You can also embed the library in any application you want: https://github.com/JohnSully/libwasm
My WasmVM project builds an interpreter too, with some more features like auto link modules, support system call by traps... etc
https://github.com/LuisHsu/WasmVM