WebAssembly (WASM) — Component Model, WASI

WASM pour performance critique, polyglot runtime, edge computing.

Use Cases

Browser — Crypto, image (Figma, Google Earth)
Edge — Cloudflare Workers, Fastly
Server — Plugins sandboxés (Envoy)
Embedded — IoT, automotive

Compilation

Rust — wasm-pack (~50KB, perf)
Go — GOOS=js GOARCH=wasm (~2MB)
C/C++ — Emscripten (legacy)
AssemblyScript — TypeScript-like

Rust to WASM

use wasm_bindgen::prelude::*;
#[wasm_bindgen] pub fn add(a: i32, b: i32) -> i32 { a + b }

wasm-pack build --target web

import init, { add } from './pkg/wasm.js';
await init(); add(2, 3);

WASI (System Interface)

rustc --target wasm32-wasi main.rs -o app.wasm
wasmtime app.wasm

Component Model

interface math { add: func(a: s32, b: s32) -> s32 }

Compose Rust/Go/C++ modules typés.

Edge (Cloudflare)

import wasm from './processor.wasm';
export default {
  async fetch(req) {
    const inst = await WebAssembly.instantiate(wasm);
    return new Response(inst.exports.process(req.body));
  }
};

Runtimes

Wasmtime — Fast, WASI
Wasmer — Universal
WasmEdge — Edge, K8s

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Voir @.claude/skills/edge-computing/SKILL.md