Live-Coding a JavaScript JIT for SerenityOS's LibJS

HN commenters cite it as a concrete example of how a skilled developer uses Copilot, mostly as fancy autocomplete for codebase-specific work.

Andreas Kling live-codes a prototype JavaScript JIT compiler for the LibJS engine used in SerenityOS and Ladybird. He builds a standalone bytecode VM, a simple interpreter, and then a simple JIT in about 80 minutes.