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+---
+title: Use Compound Components
+impact: HIGH
+impactDescription: enables flexible composition without prop drilling
+tags: composition, compound-components, architecture
+---
+
+## Use Compound Components
+
+Structure complex components as compound components with a shared context. Each
+subcomponent accesses shared state via context, not props. Consumers compose the
+pieces they need.
+
+**Incorrect (monolithic component with render props):**
+
+```tsx
+function Composer({
+  renderHeader,
+  renderFooter,
+  renderActions,
+  showAttachments,
+  showFormatting,
+  showEmojis,
+}: Props) {
+  return (
+    <form>
+      {renderHeader?.()}
+      <Input />
+      {showAttachments && <Attachments />}
+      {renderFooter ? (
+        renderFooter()
+      ) : (
+        <Footer>
+          {showFormatting && <Formatting />}
+          {showEmojis && <Emojis />}
+          {renderActions?.()}
+        </Footer>
+      )}
+    </form>
+  );
+}
+```
+
+**Correct (compound components with shared context):**
+
+```tsx
+const ComposerContext = createContext<ComposerContextValue | null>(null);
+
+function ComposerProvider({ children, state, actions, meta }: ProviderProps) {
+  return <ComposerContext value={{ state, actions, meta }}>{children}</ComposerContext>;
+}
+
+function ComposerFrame({ children }: { children: React.ReactNode }) {
+  return <form>{children}</form>;
+}
+
+function ComposerInput() {
+  const {
+    state,
+    actions: { update },
+    meta: { inputRef },
+  } = use(ComposerContext);
+  return (
+    <TextInput
+      ref={inputRef}
+      value={state.input}
+      onChangeText={(text) => update((s) => ({ ...s, input: text }))}
+    />
+  );
+}
+
+function ComposerSubmit() {
+  const {
+    actions: { submit },
+  } = use(ComposerContext);
+  return <Button onPress={submit}>Send</Button>;
+}
+
+// Export as compound component
+const Composer = {
+  Provider: ComposerProvider,
+  Frame: ComposerFrame,
+  Input: ComposerInput,
+  Submit: ComposerSubmit,
+  Header: ComposerHeader,
+  Footer: ComposerFooter,
+  Attachments: ComposerAttachments,
+  Formatting: ComposerFormatting,
+  Emojis: ComposerEmojis,
+};
+```
+
+**Usage:**
+
+```tsx
+<Composer.Provider state={state} actions={actions} meta={meta}>
+  <Composer.Frame>
+    <Composer.Header />
+    <Composer.Input />
+    <Composer.Footer>
+      <Composer.Formatting />
+      <Composer.Submit />
+    </Composer.Footer>
+  </Composer.Frame>
+</Composer.Provider>
+```
+
+Consumers explicitly compose exactly what they need. No hidden conditionals. And the state, actions and meta are dependency-injected by a parent provider, allowing multiple usages of the same component structure.