WebAssembly (Wasm) is a portable standard for bytecode, allowing code to be compiled to an efficient representation that’s amenable to just-in-time optimisation, and to be run on the operating system and runtime environment of your choice. An ever-increasing number of languages offer compilation to Wasm, and Wasm runtimes are available in major browsers and as separate programs. The existence of runtimes outside the browser, such as waSCC, opens up the possibility of using WASM as a general-purpose bytecode format, similar to Java bytecode or .NET CIL. For example, the Krustlet project provides a way to run WebAssembly modules as Kubernetes pods, performing compute work or serving HTTP requests.