Basically the thing why this would be nice, Zero, is not out yet? Many promises on their page [0] which seem interesting. I used to get exited about this idea until I went back to mostly server (phoenix liveview but without phoenix) ; cannot beat that dev experience. No js/ts is a winner for me right away, but that is personal; not having to think about frontend/backend is a win which Zero+One also seems to go after but then treating all dev as client.
Where's the code? When I click on the GitHub link, it just brings me to tamagui. Your presentation was pretty cool, but I'm not going to use a front-end framework that isn't open source.
I don't know why they don't post their Github link on the website, but it was easy to find by looking at the founders' Github accounts, which were linked on the bottom of the page.
I used to follow this space a couple of years ago and just recently found out apparently you can use NativeScript (js to native API bridge) in Cordova (Capacitor).
The added value is crossplatform compatibility with SSR, and HMR, all using Vite as the single bundler on all platforms.
They baked in their vxrn.dev project to get off of Metro and forked Expo Router to do that.
Since Expo Web has a large bundle size, requires NextJS for SSR, Solito for unified filesystem routing, and 2 bundlers: Metro as a bundler on RN plus a separate bundler like Webpack or whatnot for web.
Btw, here is a good React Native, Capacitor, NativeScript etc. overview:
[0] https://zerosync.dev/