Effect is pretty nice, I'm not sure how worth it it is for the frontend, but I've heard good things on the backend, but sadly I don't use TypeScript for backend work, mainly Rust, and would love to see something like that there. I'm not sure how much Rust's type system would make it possible though however.

I know parts of Effect like its schema are incrementally adoptable but if you use it substantially with many of its features, isn't it viral in a sense? In that you need to do things the Effect way and wrap libraries into Effect functions?

It does tend to naturally bubble upwards as you point out, but you can decide where to stop.

E.g. you could describe a complex effect that has retry, scheduling, etc and run it only once with `Effect.runFork(yourEffect)`

That's in general how teams adopt it, in general there's a champion in the team that sells using one feature, and as people get accustomed and the champion does a good work mentoring it slowly takes over whole projects.