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You know how you can render a 10,000-line diff without melting the browser? By focusing on simplicity. 🧵

After overhauling the React architecture of GitHub's "Files changed" tab, we dropped Interaction to Next Paint (INP) from ~450ms to ~100ms.

📉 React components cut from 8 to 2 per line 🔑 O(1) data access with JS Maps 🪟 Window virtualization for giant PRs