Sandbox demo
Lists and Performance
FlashList vs FlatList. Avoiding the dropped-frame trap on long scrolls.
FlatList is fine for short lists. For anything past ~50 items, switch to Shopify's FlashList — it estimates row sizes ahead and recycles cells aggressively. The difference between 60fps scrolling and a stuttering list is usually FlashList vs FlatList plus a stable estimatedItemSize.
Sandbox transcript
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The transcript is canned — no real API calls. The point is to internalize the loop: user → plan → tool → result → answer.
Check your understanding
Q1. What does estimatedItemSize do in FlashList?
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