that is a Go based thing?

best option for being able to deploy it also to native with Go is https://gioui.org but support for the wasm is a bit patchy and the devs of that project focus on the rendering system and haven't put any serious effort into widgets

https://github.com/maxence-charriere/go-app for those interested

finally someone did the declarative syntax dynamic generator, there used to be real basic ones but this is awesome

i love the immediate mode syntax of Gio but it's so easy to forget it's supposed to be the frame painter and put logic in there