Orientation

This is an outline of less technical things that will help clarify the big picture motivating the project

'Wasm' in this project means compiling Rust for --target wasm32-unknown-unknown

Before WebAssembly was a thing, there was asm.js. Asm.js uses emscripten to generate a subset of javascript that browsers could compile down to native code.

   C/C++  -> LLVM-bytecode ->  emscripten -> asm.js

Then the browser vendors all got together and agreed upon the WASM spec

   C/C++  -> LLVM-bytecode -> emscripten, binaryen -> LLVM-wasm-backend -> wasm

Rust could use the above too via --target wasm32-unknown-emscripten

   Rust  -> LLVM-bytecode -> emscripten, binaryen -> LLVM-wasm-backend -> wasm

In november 2017 the rust team announced that rust can compile to a wasm target independently of the emscripten tooling via wasm32-unknown-unknown

   Rust  -> LLVM-bytecode -> LLVM-wasm-backend -> wasm

Emscripten delivers all kinds of runtime support should your program need it, up to and including webgl api bindings and even emulating the file system in js. A typical emscripten project is a complete program that can ship with large javascript files.

wasm32-unknown-unknown on the other hand compiles small dynamic libraries. There is zero javascript produced, just .wasm binaries. This is what we are using.

Wasm Documentation

• javascript api at MDN

• Read the amazing Lin Clark

  • https://hacks.mozilla.org/2017/02/a-crash-course-in-assembly/
  • https://hacks.mozilla.org/2017/02/creating-and-working-with-webassembly-modules/
  • https://hacks.mozilla.org/2017/02/what-makes-webassembly-fast/
  • https://hacks.mozilla.org/2017/06/a-crash-course-in-memory-management/
  • https://hacks.mozilla.org/2017/07/webassembly-table-imports-what-are-they/

• https://webassembly.org/

What is serde

Serde is a serialization framework for rust.

Packaging

What about Wasm-bindgen, Wasm-pack

• https://hacks.mozilla.org/2018/04/javascript-to-rust-and-back-again-a-wasm-bindgen-tale/
• https://hacks.mozilla.org/2018/04/hello-wasm-pack/

Further Reading

• https://rustwasm.github.io/
• https://kripken.github.io/blog/binaryen/2018/04/18/rust-emscripten.html
• https://hacks.mozilla.org/2018/01/oxidizing-source-maps-with-rust-and-webassembly/
  • ^ this is a great read