Live version here: https://wasm-terminal.firebaseapp.com/
This is a small demo of running Python in the browser with a focus on implementing stdout/stderr and blocking stdin.
Python compiled to WebAssembly is supplied by Pyodide.
This demo runs Pyodide in a Web Worker so it's on a separate thread and uses SharedArrayBuffer and Atomics in javascript to allow stdin to block Python execution until the UI asynchronously resolves input in the terminal.