It’s interesting to see how cloud-native runtimes are evolving. Although containers make it simple for applications to bring their own runtimes to clouds, and offer effective isolation from other applications, they don’t offer everything we want from a secure application sandbox. Bringing your own userland solves a lot of problems, but it’s a horizontal isolation not vertical. Container applications still get access to host resources.
That’s why WebAssembly (often shortened to Wasm) has become increasingly important. WebAssembly builds on the familiar JavaScript runtime to provide a sandbox for both server-facing and user-facing code. Binaries written in familiar languages, including the memory-safe and type-safe Go and Rust, can run on Wasm in the browser and use WASI (WebAssembly System Interface) as native applications that don’t need a browser host.
