Why do they have to be eager?

react-native and react need to be present for initialisation of the environment done in react-native/Libraries/Core/InitializeCore.js - Hermes engine doesn't have event loop on its own -> no microtasks -> no timers like setImmediate or setTimeout.

they can most likely be made not eager but that would require rewriting the initialization part and maintaining it here. OOT platforms could also potentially customize it (im not sure this is the case now though)

So I'm guessing there's no promise either? Like wouldn't it help if the entrypoint itself returned a promise so that entry setup itself is asynchronous? Like my hoisted runtime experiment does.

I wonder if lynx supports event loops. 🤔
This is something I'll probably want to bake into our vm if possible

So I'm guessing there's no promise either? Like wouldn't it help if the entrypoint itself returned a promise so that entry setup itself is asynchronous? Like my hoisted runtime experiment does.

yeah that would be ideal, but that would need more tinkering. I think I tried with hoisted runtime once but didn't pursue it much further. The biggest limiting factor is maintenance of custom initialisation logic.

On the other side, @robik once had an idea of creating an extra layer between RN Core and Hermes called RN Runtime which could be a place for stuff like this. Not sure whats the status of that, maybe he can share something here as well :)

Yeah, I think this would solve this issue. The RFC is in pre-published state for now, should be up for discussions soon :)