Assemblyscript

A simple cart might look like this:

And then you can compile to a cart with:

mkdir -p cart
curl https://raw.githubusercontent.com/notnullgames/null0/refs/heads/main/carts/as/null0.ts > null0.ts
asc main.ts --optimize --target release -o "cart/main.wasm" --runtime stub
cd cart
zip -rq ../mygame.null0 .

See build.sh for an example of how I build for this example-site.