WebAssembly module as worker

I tried to deploy a WebAssembly module as worker following this
[tutorial] https://blog.cloudflare.com/announcing-wasi-on-workers. Command in tutorial is:

npx [email protected] dev my_module.wasm

.I got this error: No loader is configured for “.wasm” files: my_module.wasm.

Any idea on this problem? Thanks in advance…