Tangentially, Solid is fascinating - especially the dom-expressions backend meaning you can basically bolt compilation behaviour into anything that supports that.
The flagship feature of React 19 is a "compiler", but doesn't seem to have the main features of Forget. (inferred effect dependencies) I'm guessing it's not coming any time soon.
React 19, a library release, is completely separate from the eventual release of the React Compiler build tool (which is currently implemented as a Babel plugin wrapper around a full compiler implementation core).
That said, React Compiler will _depend_ on React 19, because it needs a new memo/caching hook that will be included in 19.
I have https://github.com/ryansolid/mobx-jsx/?tab=readme-ov-file#mo... on my list to try since I -really- like mobx for stage management (especially mobx-keystone) and am fascinated by how clean the results can be.
Though for 'real' code I still tend to default to react + mobx-keystone because for all my gripes with react it's a pretty solid Schelling Point.