It's awesome that Wasmi is fast enough to run GUI apps. I'm working on an app runtime for making highly portable GUI apps. I'm targeting wasm because it seems to strike a good balance between performance and implementation simplicity. Ideally it would be possible to run apps on a runtime hacked together by a small team or even a single person. The fact that an interpreted (if highly optimized) wasm runtime like Wasmi is clearly capable of running GUI apps is exciting.