Maomi is greatly optimized on execution speed. In most cases, there is no need to worry about it.
On the other hand, most high-level code does not need to be so fast. Don't be afraid to write simple code that is a little slower.
If there is a need of profiling, note that the release builds are much faster then debug builds (like most rust programs do).
In most cases, WebAssembly binary is bigger than JavaScript code, but it generally has a better compression rate. Do not forget to turn on HTTP compression on the generated binary.
Besides that, some code generation options have great helps to reduce the generated WebAssembly binary size. It is recommended to use the following options in Cargo.toml.