IRB on browser powered by WebAssembly. You can try irb.wasm on your browser. It works on CRuby ported to WebAssembly.
Demo: https://irb-wasm.vercel.app/
irb.wasm.-.Google.Chrome.2022-11-30.15-25-59.mp4
$ rake static/irb.wasm # You can omit the argument as default task makes static/irb.wasm
$ npm install
$ rake parcelIf you need to re-build Ruby itself (when you made a change to Ruby), clean rubies and build directories by rake deep_clean, then re-execute rake static/irb.wasm
If you just made a change to fake-gems, you only need to remove static/irb.wasm by rake clean and re-execute rake static/irb.wasm to avoid rebuilding everything.