WebAssembly integration
Slap yourself if
You think WebAssembly is a drop-in JavaScript replacement or assume calling into WASM is always faster than staying in JS.
Why this exists
Because teams integrate WebAssembly chasing speed and end up with slower apps, worse debuggability, and architectural lock-in caused by boundary costs they never modeled.
Mental model
WebAssembly is a separate execution engine with its own memory, calling conventions, and constraints. Performance comes from isolation and predictability — not magic.
- A WASM module is fetched, compiled, and instantiated by the runtime.
- JavaScript and WASM communicate through explicit imports, exports, and shared memory.
- Crossing the JS↔WASM boundary has non-trivial overhead.
- WASM code executes in a sandbox with no direct DOM or JS object access.
- Calling WASM functions too frequently from JS.
- Passing complex data structures across the boundary.
- Expecting DOM access or browser APIs inside WASM.
- Assuming WASM automatically improves startup performance.
WebAssembly integrates as a separate execution environment that can outperform JS for compute-heavy, predictable workloads, but introduces boundary and memory management costs.
- Calls WASM 'faster JavaScript'.
- Ignores boundary overhead.
- Assumes DOM access is possible.
- Frames WASM as a universal optimization.
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