Load all the component tree with dynamic without ssr. anyway i dont see how loading state is related (localstorage is not async) .You need to read it in useEffect to avoid hydration problems. or you can use Zustand store read that data and draw using zustand subscription in your componentes anyway you gonna need double render (you are using a hook to read values after you render the initial UI) unless you lazyload the components (dynamic again) after you read and pass the data via prop. No idea what you storing in localstorage but i prefer store evrything i can in database for persistence across devices.

how do I define that at the layout though when the subtree is just {children}

Sorry didnt notice your response. you dont since children is passed by router as far i know you cant load children using dynamic you need to load a dynamic component with Dynamic but since you seem to dont want use server components at all what is the point of use app directory. If you want something fully client maybe you should try pages directory. But dont forget you wont have SEO using lazy load. Im having hard time to imagine what you doing exactly and why you need such a strong use of localstorage (i wont even use that for shopping cart) because that kinda data is important to be in server for client suggestion.

It’s an electron app it’s not a typical website