Split context providers

The problem

One AppContext holds theme, user, and both setters. Toggling theme re-renders every consumer, including the profile badge that only reads user. memo on the badge still sees a new context value object.

The pattern that fixes it

Split providers (and values) by update rate: ThemeContext vs UserContext. A consumer of user does not subscribe to theme. useMemo the value object. Selectors / useContextSelector are the next step when one context is still too wide.

Keep learning

• Previous: key as state reset
• Next: useImperativeHandle
• Related: Moving state down
• Related: Children as props
• Related: Render props
• Related: Nested component types
• Related: key as state reset
• Related: useImperativeHandle

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