What is incremental static regeneration (ISR) in Next.js?
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
Incremental Static Regeneration is a technique in Next.js that allows you to update static pages at runtime without rebuilding the entire site.
This feature introduces a seamless way to serve both static and dynamic content by revalidating and regenerating pages in the background.
export async function getStaticProps() {
const res = await fetch("https://api.github.com/repos/vercel/next.js");
const repo = await res.json();
return { props: { repo }, revalidate: 1 };
}
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.