Virtualization

Summary

Rendering only the visible portion of a very long list or table (plus a small buffer), rather than every item at once — essential for smooth scrolling with thousands of rows.

• 1Render a 10,000-item list normally and observe the scroll jank.
• 2Rebuild it using a virtualization library (e.g. TanStack Virtual) and compare.
• 3Learn the core idea: only mount DOM nodes for what's actually visible.