ARM64js – ARM64 emulator that runs Alpine Linux in a web browser

Running a terminal application inside a web page requires a whole operating system, and one approach is to emulate a computer in the browser. According to its author's article, ARM64JS is an ARMv8-A processor emulator written in Rust and compiled to WebAssembly, which boots a real Alpine Linux system inside the page. Users can install packages and try terminal (TUI and CLI) programs without installing anything locally.

The article explains why a browser needs extra pieces to make that useful. Alpine's package mirrors do not send the headers browsers require for cross-site requests, so a small proxy adds them. Browsers cannot open raw TCP connections, so network traffic goes through a WebSocket-to-TCP proxy. Virtual machine snapshots are kept in the browser's local storage so a reload does not lose state. The author describes the speed as comparable to an early-2000s PC and says it cannot compile Rust projects, so this suits trying lightweight programs rather than heavy development work.