React Digest
React Digest
#542 – February 01, 2026
the hook doesn't prevent race conditions or reduce boilerplate code
useOptimistic won't save you
8 minutes by Colum Kelly
Colum explains how optimistic UI updates the interface immediately when users interact with it, while the actual operation runs in the background. This makes apps feel faster by avoiding network delays. React 19's useOptimistic hook was meant to simplify this pattern, but it actually makes things more complex. The hook doesn't prevent race conditions or reduce boilerplate code, making it difficult to implement correctly without bugs.
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Adapting library logic for React compiler
4 minutes by Corbin Crutchley
As the maintainer of TanStack Form Corbin shares his discovery of React Compiler compatibility issues when updating his library. Corbin's code worked fine in parent components but broke when passing scroll position data to child components. The problem was mutating objects returned from useState, which React Compiler couldn't optimize properly. The solution involved avoiding mutations and letting the compiler handle performance optimizations instead.
Inside Turbopack: Building faster by building less
6 minutes by Anthony Shew
Turbopack makes code compilation much faster by using smart caching and incremental computation. Instead of rebuilding everything when code changes, it only recomputes the parts that actually need updating. The system uses "value cells" to automatically track dependencies between different pieces of code, similar to how spreadsheet cells work. This fine-grained approach lets Turbopack skip unnecessary work and deliver instant builds for large web applications.
Open sourcing our microfrontend React bridge
1 minute by Alex O'Callaghan
Alex presents an open source package that helps to upgrade React versions across multiple micro-frontends. The package solves re-rendering issues with existing solutions and allows the 28 micro-frontends to upgrade React independently. It provides TypeScript support and works with React 17 and 18+.
React Slot and asChild composition pattern
5 minutes by Boda
In React, we have seen several composition patterns for creating advanced and reusable components, for example, the Higher Order Components (HOCs) and the as prop. Boda explains the recent asChild prop and the Slot pattern popularised by Radix UI.
And the most popular article from the last issue was: