WebAssembly (abbreviated Wasm) is a binary instruction format for a stack-based virtual machine. Wasm is designed as a portable target for compilation of high-level languages like C/C++/Rust, enabling deployment on the web for client and server applications. from WebAssembly.org
WebAssembly has huge implications for the web platform — it provides a way to run code written in multiple languages on the web at near native speed, with client apps running on the web that previously couldn’t have done so. from Mozila.org
Since WebAssembly is available in node (v8.x+), I experimented in Node-RED environment
square.wasm was pre-built wasm (originally in C).
Welcome to Node-RED
===================
9 Aug 13:31:36 - [info] Node-RED version: v0.18.6
9 Aug 13:31:36 - [info] Node.js version: v8.11.2
9 Aug 13:31:36 - [info] Windows_NT 10.0.10586 x64 LE