next.js and react-internal.js are plain re-exports of base, so no rules-of-hooks checking was active anywhere despite three React apps and core-ui. Wire eslint-plugin-react-hooks in base.js scoped to **/*.tsx (non-React packages untouched). Fixes the one violation it surfaced: web-tanstack's root route called Route.useLoaderData inside an anonymous component callback — extracted to a named RootComponent. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>