This is a template for a ruby.wasm app without any requirements.
Just edit main.rb and index.html with your own code.
git clone https://github.com/Largo/rubyWasmTemplate
./serve.sh
open localhost:8080 in your browser
npm install -g yarn
yarn install
yarn run
Not necessary, because ruby-app.wasm comes included.
git clone https://github.com/Largo/rubyWasmTemplate
cd rubyWasmTemplate
git clone https://github.com/largo/ruby.wasm
./build.sh