I tried out WASM for a very small project once. This was built from a freestanding C source file (no libraries at all, not even the standard library). Zig was

I tried out WASM for a very small project once. This was built from a freestanding C source file (no libraries at all, not even the standard library). Zig was the C compiler used to build the program. And I was able to get things working with an understanding of the whole system. You could instantiate the WASM from either a file, or from a byte array, pass in the byte array that held 'system memory' for the WASM program, call the WASM functions from the JavaScript code, and see results of making the function calls. The WASM binary was under 3KB in size. Now once you want to use libraries, everything light and small about WASM goes out the window. You're at the mercy of how efficiently the library code was implemented, and how many dependencies they used while doing so.