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+---
+title: Create Explicit Component Variants
+impact: MEDIUM
+impactDescription: self-documenting code, no hidden conditionals
+tags: composition, variants, architecture
+---
+
+## Create Explicit Component Variants
+
+Instead of one component with many boolean props, create explicit variant
+components. Each variant composes the pieces it needs. The code documents
+itself.
+
+**Incorrect (one component, many modes):**
+
+```tsx
+// What does this component actually render?
+<Composer isThread isEditing={false} channelId="abc" showAttachments showFormatting={false} />
+```
+
+**Correct (explicit variants):**
+
+```tsx
+// Immediately clear what this renders
+<ThreadComposer channelId="abc" />
+
+// Or
+<EditMessageComposer messageId="xyz" />
+
+// Or
+<ForwardMessageComposer messageId="123" />
+```
+
+Each implementation is unique, explicit and self-contained. Yet they can each
+use shared parts.
+
+**Implementation:**
+
+```tsx
+function ThreadComposer({ channelId }: { channelId: string }) {
+  return (
+    <ThreadProvider channelId={channelId}>
+      <Composer.Frame>
+        <Composer.Input />
+        <AlsoSendToChannelField channelId={channelId} />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.Submit />
+        </Composer.Footer>
+      </Composer.Frame>
+    </ThreadProvider>
+  );
+}
+
+function EditMessageComposer({ messageId }: { messageId: string }) {
+  return (
+    <EditMessageProvider messageId={messageId}>
+      <Composer.Frame>
+        <Composer.Input />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.CancelEdit />
+          <Composer.SaveEdit />
+        </Composer.Footer>
+      </Composer.Frame>
+    </EditMessageProvider>
+  );
+}
+
+function ForwardMessageComposer({ messageId }: { messageId: string }) {
+  return (
+    <ForwardMessageProvider messageId={messageId}>
+      <Composer.Frame>
+        <Composer.Input placeholder="Add a message, if you'd like." />
+        <Composer.Footer>
+          <Composer.Formatting />
+          <Composer.Emojis />
+          <Composer.Mentions />
+        </Composer.Footer>
+      </Composer.Frame>
+    </ForwardMessageProvider>
+  );
+}
+```
+
+Each variant is explicit about:
+
+- What provider/state it uses
+- What UI elements it includes
+- What actions are available
+
+No boolean prop combinations to reason about. No impossible states.