Never write a DIY price-flash loop again. Headless React hook that tracks which cells in a data table changed value and exposes 'up' | 'down' | null flash direction per cell — drops in alongside MUI DataGrid, TanStack Table, react-data-grid, or any renderer in under 5 lines. Zero runtime dependencies. . NaN-safe — fields with undefined or non-numeric values are silently ignored; no spurious flashes on missing data. Timer reset on rapid updates — the clear-timer resets on every new value so the flash never cuts short mid-burst. Zero runtime dependencies — single peer dependency: react >= 16.8. Bundle is = 16.8. No @types/ package needed — types are bundled. Notes Stable public API from this release forward; breaking changes will bump the major version. MIT license. Full changelog: CHANGELOG.md