Welcome to the crux of the WebAssembly universe - the low-level architecture. Just like the grand, sophisticated robotics, the nuances hidden under your everyday websites are crafted intricately.

WebAssembly, much like the hardware of a computer, comprises of various components each playing a distinct role to ensure near-native performance. The essence of running high-level languages like C++, Rust in a web application setting comes down to these low-level constructions.

The first 'brick in the wall' is the binary format. This format allows WebAssembly to boast its compact size, speedy download time, and efficient execution. It consists of a sequence of bytes, encoding instruction, and data which interpreters can understand and execute.

Next up, we have the code section that contains a vector of function bodies. Each body encodes a function's locals and body expression. Taking an aptitude towards C++, WebAssembly also provides the ability to define functions with local variables and argument stacking.

To manage and manipulate linear memory, WebAssembly employs 'memory instructions'. This memory is given in pages, wherein 1 page = 64KiB. Our use of IndexedDB or localStorage in Javascript is quite similar to the implementation of linear memory in WebAssembly.

Lastly, WebAssembly also defines structured control flow. Instead of using labels for branching, structured control uses nesting constructs like blocks, loops, and conditionals. This ensures top-notch performance while still adhering to the secure and safe code execution principles.

Let's use a code snippet below to define a function in C++, compile it to WebAssembly, and observe some of these components in action.

Keep in mind, as a senior engineer, understanding these low-level structures is quintessential in leveraging the power of WebAssembly to the fullest.

xxxxxxxxxx

#include <emscripten/emscripten.h>

using namespace std;

​

extern "C" {

​

int EMSCRIPTEN_KEEPALIVE myFunction(int x, int y) {

  return x + y;

}

​

int main() {

  myFunction(5, 10);

  return 0;

}

}