Mastering Composition in React | React Universe Conf 2025

Composition is React’s most powerful tool, but it’s also one of the most misunderstood.

At React Universe Conf 2025, Fernando Rojo, Head of Mobile at Vercel, demonstrates how composition can scale your codebase from a single component to thousands, while making it easier for both humans and AI to work in.

Skip the intro ⏩ 0:39

🔹 Why “boolean prop hell” (e.g. `isEditing`, `shouldRenderButton`) makes components unmaintainable.
🔹 How real-world UIs like Slack’s composer quickly become messy when built with conditional props.
🔹 A compositional approach that replaces bloated monoliths with small, flexible components.
🔹 Techniques for handling state management, whether ephemeral (local) or global (synced across devices).
🔹 How composition makes codebases more AI-friendly, enabling developers to pair program effectively with AI tools.
🔹 A special live AI prompt to close the talk.

If you’ve ever wrestled with sprawling conditionals and rigid components, this talk will help you fall in love with React again.

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