Virtualize long lists and tables
SkillSearchList-virtualization is a skill for AI agents that guides code review and fixes for long lists, tables, grids, and feeds. It helps confirm that slow rendering is actually caused by DOM size before introducing virtualization, since small lists usually do not need the added complexity. When v
Available today. Use it from your connected AI after setup.
No other account needed.
Have an agent that can load skills, and a codebase with lists, tables, or feeds to review.
Then ask your AI: use the Virtualize long lists and tables skill
What your AI can do with it
- Flag views that render every item at once, creating DOM, memory, or scroll-performance iss
- Introduce list or table virtualization so only visible rows plus overscan render
- Preserve item sizing, keyboard navigation, sticky headers, and selection behavior when win
- Measure scroll smoothness, memory use, and DOM node count before and after the change
- Explain virtualization tradeoffs around measurement and accessibility
- Review collection components, data tables, infinite feeds, and dashboards for excessive DO
Getting started
- Have an agent that can load skills, and a codebase with lists, tables, or feeds to review.
- Add the list-virtualization skill to the agent's available skills.
- Ask the agent to review dashboards, admin tables, search results, or feeds with many repeated items.
- Have the agent confirm the bottleneck is DOM or rendering cost before applying virtualization.
- Apply the recommended fix and verify sizing, keyboard access, and screen-reader semantics are preserved.
What this skill tells your AI
The instructions your AI receives, as published by thedaviddias/front-end-checklist in skills/list-virtualization/SKILL.md and read by ahel’s review.
Rendering hundreds or thousands of rows at once wastes memory and makes style calculation, layout, and painting more expensive. Virtualization keeps large collections responsive by limiting the number of mounted nodes.
Quick Reference
- Render only what is visible plus a small overscan buffer instead of the entire list
- Use virtualization when repeated rows or cards push DOM size and layout cost too high
- Preserve item sizing, keyboard access, and screen-reader semantics when windowing content
- Measure scroll smoothness, memory use, and DOM node count before and after the change
Check
Inspect long lists, tables, grids, and feeds for places where the UI renders every item at once. Flag views where the number of mounted rows or cards is large enough to create DOM, memory, or scroll-performance issues.
Fix
Introduce list or table virtualization so only the visible rows plus overscan render, while preserving sizing, keyboard navigation, and any required sticky headers or selection behavior.
Explain
Explain list virtualization, why it improves performance for large collections, and the tradeoffs engineers need to watch for around measurement and accessibility.
Code Review
Inspect collection components, data tables, infinite feeds, and dashboards. Flag places where rendering the full dataset creates excessive DOM nodes or scroll jank, and verify the virtualization strategy still preserves item identity, semantics, and expected interactions.
For full implementation details, code examples, and framework-specific guidance,
see references/rule.md.
Rule page: https://frontendchecklist.io/en/rules/performance/list-virtualization
Signals
- GitHub stars
- 74k
- Forks
- 7k
- Last commit
- Aug 2026
Questions
- When should list virtualization be used?
- Use it when repeated rows or cards push DOM size and layout cost too high in dashboards, admin tables, search results, or feeds. Confirm the bottleneck is DOM or rendering cost first, because small lists usually do not need the added complexity.
- What does virtualization actually change?
- Instead of rendering the entire list, only the visible rows plus a small overscan buffer are mounted, which limits DOM nodes and reduces style calculation, layout, and painting cost.
Advanced
- Item type
- skill
- Key
list-virtualization- Source
- github.com/thedaviddias/front-end-checklist