As Go 1.21 is not released yet - please use gotip to install the main branch version: Install Prerequisites:
go install http://golang.org/dl/gotip@latest
gotip download
brew install wazero
Build the Wasm module (called evaluator):
cd evaluator; GOARCH=wasm GOOS=wasip1 gotip build -o evaluator.wasm evaluator.go; cd ..
Run:
gotip run host.go