alt Hacker NewsMy 2 cents: I am not an experienced React dev, but the React compiler came out recently with React 19, which is supposed to do the same thing as Svelte's - eliminate unnecessary DOM modifications by explicitly tracking which components rely on what state - thus making useMemo() unnecessary.
Since the article still references useMemo(), I wonder how up-to-date the rest of the article is.
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useMemo is for maintaining calculations of dependencies between renders, renders generally caused by state changes. React always tries to track state changes, but complicated states (represented by deep objects) can be recalculated too often - not sure if React 19 improves this, don't think so when reading documentation.
on edit: often useMemo is used by devs to cover up mistakes in rendering architecture. I believe React 19 improves stuff so you would not use useMemo, but not sure if it actually makes useMemo not at all useful.
React has always been tracking what component relies on what state, independent of the compiler. That is one of the reason the rule-of-hook has to exist - it tracks if a component calls useState() and thus knows the according setState function that manipulates that particular state.
Idk why people claim React is bloat, especially since you can switch to Preact (4kb) most of the time without changes if filesize is an issue for you.