Framework support

scrollsheet is SSR-safe by design, not by special-casing. The dialog only exists once JS runs on the client: it’s gated behind a mount flag that starts false and flips in a useEffect, so the server render and the first client render before hydration finishes produce identical markup, no dialog, just your trigger.

Compatibility table

Framework	Works out of the box	Notes
Next.js App Router	Yes, with 'use client'	See the caveat below: the file that renders <Sheet.Root> needs the directive too, not just scrollsheet’s own.
Next.js Pages Router	Yes	No RSC boundary to worry about; "use client" is inert but harmless.
Remix / React Router v7	Yes	Same SSR + hydration shape scrollsheet already handles.
Astro	Yes	See the caveat below.
Vite (SPA, no SSR)	Yes	renderToString never runs, so this is the simplest case.

Next.js App Router

Sheet.Root, Sheet.Trigger, and the rest are interactive: state, event handlers, real DOM refs. They only run in a Client Component. scrollsheet’s own "use client" banner on every dist chunk is not enough by itself: a Server Component that imports Sheet and renders <Sheet.Root> gets one opaque client reference for the whole Sheet object, so Sheet.Root reads as undefined there and React throws Element type is invalid. Add 'use client' to the top of whatever file renders it, the same rule as any other interactive component in App Router.

Astro caveat

An island only hydrates if you give it a client:* directive (client:load, client:idle, client:visible, etc.). Put one on whatever component renders your Sheet.Trigger, same as any interactive Astro component; the mount gate works identically whichever one you pick.