Learn the basics of WebAssembly and see how to compile a simple C function without extra tooling, highlighting the manual memory management required.
Emscripten acts as a toolchain that emulates an OS environment, providing a standard library and tools like Embind to easily bind C++ classes to JavaScript.
Use Emscripten's macros like EM_JS to call JavaScript from C++ and proxy heavy computations to a web worker to keep the main UI thread responsive.
WebAssembly is ideal for CPU-bound tasks or for reusing existing native C, C++, or Rust libraries in the browser, as seen in apps like Figma and SQL.js.
A benchmark shows that while scalar operations in Wasm are only slightly faster than JavaScript, using SIMD instructions provides a significant performance boost for numerical computations.
See how the native Bitcoin Core library libsecp is compiled to WebAssembly using Emscripten's AutoTools wrappers, resulting in a 9x performance increase over its JavaScript equivalent.
Evaluate the trade-offs by understanding when to use Wasm for performance gains versus the costs of maintenance, memory management, and increased bundle size.
The Privymix project uses WebAssembly not for speed, but to maintain a single C++ client library for cryptography that can be deployed across multiple environments.
Learn best practices for maintaining Wasm libraries, including API design with TypeScript wrappers, CI version pinning, and using Emscripten flags to reduce bundle size.
A final review of the core concepts, emphasizing that WebAssembly is a powerful tool for reusing native code and handling CPU-bound work, not a simple "go faster" wrapper.
Jobs that call for the skills explored in this talk.