Bundler configuration
NCC
In case you are NCC you need to define the opaque package as external. Otherwise the bundler will mangle with the internal function names binding to WebAssembly and the module becomes unusable.
Example Script
ncc build ./src/index.ts -o build --external @serenity-kit/opaque
Make sure that the folder that gets deployed includes a node_modules/@serenity-kit/opaque
directory containin the actual module.