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Sweep 22 Oct 2026 · 21:04Z Build v2.1.309 528 read Stable v2.1.308 Latest v2.1.309 Next v2.1.309 Feeds RSS JSON llms.txt llms-full.txt Unofficial
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Claude Code v2.1.15 ·

React Compiler Memoization

Entry
JSON All of v2.1.15
EntryKind: in v2.1.15,
ChangesSection of the release
What

The entire UI layer has been updated to use React Compiler's automatic memoization through useMemoCache.

Details
  • In v2.1.14: Only 1 reference to react.memo_cache_sentinel (the definition in React internals)
  • In v2.1.15: 736 usages across UI components
  • A new shared e() function wraps useMemoCache for use across all components
  • This provides automatic fine-grained memoization without manual useMemo/useCallback calls
  • Should improve rendering performance by avoiding unnecessary re-renders
Evidence

e = function(A) { return dn5.H.useMemoCache(A) } at line 92039, 736 occurrences of Symbol.for("react.memo_cache_sentinel") checks throughout UI code

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

See this entry in the whole of v2.1.15 →

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