Build vs Runtime

Definition

Build time is when Next.js generates static pages before deployment. Runtime is when pages render dynamically during user requests.

Why Important

• Performance optimization
• Choose correct rendering strategy

When It Happens

• Build → During deployment
• Runtime → During user request

Real-World Example

Blog posts generated at build time, dashboard data rendered at runtime.

Interview Tip

Build time improves speed via static pages, runtime enables dynamic content.