Every AI chat app has the same bug — scrollbar jitter when streaming tokens. ZeroJitter is a React component that renders streaming LLM text on instead of the DOM. The result: → 0 layout reflows (DOM causes 1 per token) → 60fps locked (DOM drops to 45-58fps) → <1ms layout time (DOM: 0.3-2ms) → Zero dependencies → Full accessibility (aria-live mirror) → International text (CJK, BiDi, Thai, emoji) Text measurement happens in a Web Worker. The main thread just paints pixels.