WebAssembly is quietly making browsers capable

Wasm stopped being a curiosity the moment shipping a real compute workload to the browser became cheaper than running it on your servers.

Where it pays - Media processing: transcode, trim and filter without an upload - On-device inference for small models - Data-heavy UIs querying a local analytics engine - Porting an existing C++ or Rust engine to the web

What you get back Zero per-user compute cost, no upload latency, and data that never leaves the device — which turns several compliance conversations into non-conversations.

The honest costs Bundle size is real. Cold-start compile time is real. Debugging across the JavaScript boundary is worse than either side alone. Budget for streaming compilation and a lazy load behind an interaction.

Rule of thumb If the payload is large and the computation is heavy, ship the code to the data. Otherwise keep it on the server.