What is the `metadata` export in the App Router and how do you use it?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of Next.js conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
The App Router supports a metadata export (or metadata.js/ts) to define route-level metadata like title, description, open graph tags and robots. You can export a static object or an async function that returns metadata.
// app/blog/[slug]/page.js
export const metadata = {
title: "Blog Post",
description: "A useful blog post",
};
export default function PostPage() {
/* ... */
}
Candidate Response Strategy & Interview Tips
- Start with a concise one-sentence summary: Deliver a direct, confident answer first before expanding into nuances.
- Demonstrate real-world trade-offs: Discuss where this approach excels and when you would avoid it in production systems.
- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
- Prepare for interviewer follow-ups: Technical hiring panels frequently probe deeper into concurrency, backward compatibility, or alternative libraries.