WebAssembly Design Principles and Use Cases

Four core design assumptions

1. Don't trust the executed code — WASM runs in the browser, an untrusted environment, so it's sandboxed by design. Contrast with Java, where opening a socket (new Socket(...)) is trivial — WASM can't allow that kind of direct access.
2. Support any language — not automatic, requires the community to target the instruction set. Given a stable instruction set, language support is just a matter of time.
3. Be cross-platform — must run across Windows, Linux, macOS, Android, iOS, etc., despite each platform having its own native instruction set.
4. Be fast — both at execution and at startup, despite being a binary format that needs parsing before it runs.

Use cases

Inside the browser:

• Near-native performance for low-level languages (C/C++/Rust) compiled to WASM
• Music and video processing
• CAD and 3D modeling
• Games
• Creative tools like Figma, Photoshop

Outside the browser:

• Cloud computing
• IoT devices
• Server-side applications
• Desktop and mobile applications

Reference

• WebAssembly design documentation
• WebAssembly use cases