Firefox in WebAssembly

In plain words

Firefox in WebAssembly is the complete Firefox browser compiled to run inside a web page's canvas element, including the Gecko engine, UI components, and SpiderMonkey JavaScript engine. All rendering happens in WebAssembly with end-to-end encryption via the WISP protocol for TCP-over-websockets. It features an experimental WASM-to-JavaScript JIT compiler for potential performance improvements. This project demonstrates WebAssembly's capabilities as a proof of concept rather than a practical browser replacement.

written from the facts on this page · September 2026

From the sources

The Gecko engine compiled to WebAssembly. The real Firefox interface, rendering entirely inside this browserfrom developer.puter.com

In the maker’s words, at launch

This is the entire Firefox browser rendering to a <canvas> element. Gecko, all UI components, and the Spidermonkey JS engine are all compiled and running in WebAssembly. Here are a few things you might find interesting: - This is fully end to end encrypted! We use the WISP protocol for TCP-over-websockets. - There is…

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