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Score 0 / 0 answered · 21 total
Q1In `app/`, why does adding a `loading.tsx` next to a `page.tsx` change what gets streamed?Core (App Router)
Q2A Server Component imports a component from a file marked `"use client"` and renders it as a normal child element. What ships to the browser?Core (App Router)
Q3You have `@team` and `@analytics` parallel route slots under a layout in Next 16. The build fails with a missing-fallback error. What's missing?Core (App Router)
Q4With `cacheComponents: true` in `next.config.ts`, a component calls `headers()` directly and is NOT wrapped in `<Suspense>`. What happens?Rendering & Caching
Q5What determines the cache key for a function marked `"use cache"`?Rendering & Caching
Q6Without `cacheComponents` enabled (the older default model), what's the default caching behavior of `fetch()` in a Server Component?Rendering & Caching
Q7A Server Function (`"use server"`) is only ever called from a `<form action={...}>` in the UI. Is it safe to skip an auth check inside it?Data & Server Actions
Q8In Next 16, what's new about `revalidateTag()` compared to earlier versions?Data & Server Actions
Q9Inside a Server Action, you want the current request to immediately see the effect of a cache invalidation (read-your-writes), not just eventually. Which API is designed for that?Data & Server Actions
Q10You submit two `<form action={fnA}>` and `<form action={fnB}>` in quick succession from the client. How does Next 16 dispatch these Server Functions?Routing
Q11You rename `middleware.ts` to `proxy.ts` and rename the exported function to `proxy` for a Next 16 upgrade. What else changes in behavior?Routing
Q12A page reads `params` and `searchParams` from its props. In Next 16, what type are they?Routing
Q13What's the default and stable bundler for both `next dev` and `next build` in Next 16?Performance
Q14You wrap a slow, non-deterministic operation (e.g. reading `Math.random()` or a timestamp) in `connection()` from `next/server` inside a cached component. What does that achieve?Performance
Q15Why does swapping a large `<img>` for `next/image` typically improve LCP and CLS together?Performance
Q16Where is the most reliable place to enforce that a user is authenticated before rendering a protected Server Component's data?Auth
Q17A Server Action deletes a resource by `id` passed from a hidden form field. What's the critical check missing if the code only verifies the user is logged in?Auth
Q18You want to unit test a Server Component that's an `async function` awaiting a data call. What's the practical approach?Testing
Q19You upgrade to Next 16 and your CI step `next lint` starts failing with 'command not found'. Why?Testing
Q20A teammate reads a secret with `process.env.STRIPE_SECRET_KEY` inside a file that has `"use client"` at the top. What happens?Security
Q21Why is a Content-Security-Policy nonce generated per-request (e.g. in `proxy.ts`) rather than hard-coded, when using strict CSP with inline scripts?Security